| Summary of other intangible assets | 
 
		
			
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						Gross 
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						Less 
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						Net 
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				| 
					 
						  
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				 | 
				
					 
						  
				 | 
				
					 
						Carrying 
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						Accumulated 
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						Carrying 
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						Amount  
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						Amortization  
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						Amount  
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				| 
					 
						December 31, 2015 
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						Indefinite-lived intangibles: 
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						Trademark and tradenames 
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				 | 
				
					 
						$ 
				 | 
				
63,600
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
					 
						  - 
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
63,600
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				| 
					 
						Amortizable intangibles: 
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				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
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				| 
					 
						Dealer network 
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				 | 
				
					 
						  
				 | 
				
80,000
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				 | 
				
					 
						  
				 | 
				
47,000
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				 | 
				
					 
						  
				 | 
				
33,000
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				| 
					 
						Customer relationships 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
19,120
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
3,129
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				 | 
				
					 
						  
				 | 
				
15,991
				 | 
			 
			
				| 
					 
						Patents 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
19,636
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
8,269
				 | 
				
					 
						  
				 | 
				
					 
						  
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11,367
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				| 
					 
						Noncompete agreements 
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				 | 
				
					 
						  
				 | 
				
7,140
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				 | 
				
					 
						  
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5,573
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				 | 
				
					 
						  
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1,567
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				| 
					 
						Trademarks 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
5,459
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				 | 
				
					 
						  
				 | 
				
3,337
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				 | 
				
					 
						  
				 | 
				
2,122
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				| 
					 
						Backlog 
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				 | 
				
					 
						  
				 | 
				
200
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
200
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  - 
				 | 
			 
			
				| 
					 
						License 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
20
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
20
				 | 
				
					 
						  
				 | 
				
					 
						  
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						  - 
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						Amortizable intangibles, net 
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131,575
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67,528
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64,047
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						Total 
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						$ 
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195,175
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						$ 
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67,528
				 | 
				
					 
						  
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						$ 
				 | 
				
127,647
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				 | 
			 
			
				| 
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						Gross 
				 | 
				
					 
						  
				 | 
				
					 
						Less 
				 | 
				
					 
						  
				 | 
				
					 
						Net 
				 | 
			 
			
				| 
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						Carrying 
				 | 
				
					 
						  
				 | 
				
					 
						Accumulated 
				 | 
				
					 
						  
				 | 
				
					 
						Carrying 
				 | 
			 
			
				| 
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
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						Amount  
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				 | 
				
					 
						Amortization  
				 | 
				
					 
						  
				 | 
				
					 
						Amount  
				 | 
			 
			
				| 
					 
						December 31, 2014 
				 | 
				
					 
						  
				 | 
				
					 
						  
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				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
			 
			
				| 
					 
						Indefinite-lived intangibles: 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
			 
			
				| 
					 
						Trademark and tradenames 
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
63,600
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
					 
						— 
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
63,600
				 | 
			 
			
				| 
					 
						Amortizable intangibles: 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
			 
			
				| 
					 
						Dealer network 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
80,000
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
43,000
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
37,000
				 | 
			 
			
				| 
					 
						Customer relationships 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
19,120
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
1,990
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
17,130
				 | 
			 
			
				| 
					 
						Patents 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
19,636
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
7,121
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
12,515
				 | 
			 
			
				| 
					 
						Noncompete agreements 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
7,140
				 | 
				
					 
						  
				 | 
				
					 
						  
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5,050
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
2,090
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				| 
					 
						Trademarks 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
5,459
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
2,985
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
2,474
				 | 
			 
			
				| 
					 
						Backlog 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
200
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  - 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
200
				 | 
			 
			
				| 
					 
						License 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
20
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
20
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  - 
				 | 
			 
			
				| 
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
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				 | 
				
					 
						  
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				| 
					 
						Amortizable intangibles, net 
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
131,575
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
60,166
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
71,409
				 | 
			 
			
				| 
					 
						  
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				 | 
			 
			
				| 
					 
						Total 
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
195,175
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
60,166
				 | 
				
					 
						  
				 | 
				
					 
						$ 
				 | 
				
135,009
				 | 
			 
			
				| 
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
				 | 
				
					 
						  
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				 | 
			 
		  
		
			 
		 
 
  
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