Quarterly report pursuant to Section 13 or 15(d)

Changes in Accumulated Other Comprehensive Loss by Component - Rollforward (Details)

v3.8.0.1
Changes in Accumulated Other Comprehensive Loss by Component - Rollforward (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Changes to accumulated other comprehensive loss by component    
Balance at the beginning of the period $ (6,572) $ (6,672)
Other comprehensive earning (loss) before reclassifications 711 (189)
Amounts reclassified from accumulated other comprehensive loss 113 155
Balance at the end of the period (5,748) (6,706)
Unrealized Net Loss on Interest Rate Swap    
Changes to accumulated other comprehensive loss by component    
Balance at the beginning of the period (1,328) (1,195)
Other comprehensive earning (loss) before reclassifications 711 (189)
Amounts reclassified from accumulated other comprehensive loss 21 60
Balance at the end of the period (596) (1,324)
Other Postretirement Benefit Liability    
Changes to accumulated other comprehensive loss by component    
Balance at the beginning of the period 1,392 937
Amounts reclassified from accumulated other comprehensive loss (38) (17)
Balance at the end of the period 1,354 920
Pension Liability    
Changes to accumulated other comprehensive loss by component    
Balance at the beginning of the period (6,636) (6,414)
Amounts reclassified from accumulated other comprehensive loss 130 112
Balance at the end of the period $ (6,506) $ (6,302)