Accumulated Other Comprehensive Loss (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balance at December 31, 2015	$ (28,808)
Other comprehensive income before reclassifications	(963)
Amounts reclassified from accumulated other comprehensive loss	188
Net current-period other comprehensive loss	(775)
Balance at June 30, 2016	(29,583)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balance at December 31, 2015	(1,357)
Other comprehensive income before reclassifications	(963)
Amounts reclassified from accumulated other comprehensive loss	188
Net current-period other comprehensive loss	(775)
Balance at June 30, 2016	(2,132)
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax
Balance at December 31, 2015	(27,451)
Other comprehensive income before reclassifications	0
Amounts reclassified from accumulated other comprehensive loss	0
Net current-period other comprehensive loss	0
Balance at June 30, 2016	$ (27,451)