Quarterly report pursuant to Section 13 or 15(d)

Revenue Recognition (Contract Balances) (Details)

v3.10.0.1
Revenue Recognition (Contract Balances) (Details)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
USD ($)
Jun. 30, 2018
USD ($)
Changes in contract liabilities    
Balance at Beginning of Period $ 2,219 $ 2,048
Additions 4,351 6,171
Deductions (3,254) (4,903)
Balance at End of Period 3,316 3,316
Contract assets 0 0
Revenue recognized included in contract liabilities at the beginning of the period $ 1,106 $ 1,385