Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss), beginning balance	$ (30,798)	$ (18,239)	$ (49,638)	$ (18,712)
Amounts reclassified from accumulated other comprehensive income	(3,259)	472	15,581	945
Accumulated other comprehensive income (loss), ending balance	(34,057)	(17,767)	(34,057)	(17,767)
Amounts reclassified from accumulated other comprehensive loss:
Actuarial costs (reclassified to salaries, wages, and benefits)	393	116	1,219	374
Prior service costs (reclassified to salaries, wages, and benefits)	(225)	2	(305)	6
Foreign currency translation related to pension and postretirement plans	1,094	454	2,069	676
Remeasurements	(1,380)		16,491
Income tax provision AOCI expense	(3,141)	(100)	(3,893)	(111)
Amounts reclassified from accumulated other comprehensive income	(3,259)	472	15,581	945
Pension Plan [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss), beginning balance	(38,996)	(20,312)	(40,160)	(20,429)
Amounts reclassified from accumulated other comprehensive income	885	421	2,049	538
Accumulated other comprehensive income (loss), ending balance	(38,111)	(19,891)	(38,111)	(19,891)
Amounts reclassified from accumulated other comprehensive loss:
Actuarial costs (reclassified to salaries, wages, and benefits)	304	57	935	158
Prior service costs (reclassified to salaries, wages, and benefits)	11	11	33	33
Foreign currency translation related to pension and postretirement plans	797	453	1,502	458
Remeasurements	0		0
Income tax provision AOCI expense	(227)	(100)	(421)	(111)
Amounts reclassified from accumulated other comprehensive income	885	421	2,049	538
Post Retirement Plan [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Amounts reclassified from accumulated other comprehensive loss:
Remeasurements	(1,380)		16,491
Post Retirement Plan [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive income (loss), beginning balance	8,198	2,073	(9,478)	1,717
Amounts reclassified from accumulated other comprehensive income	(4,144)	51	13,532	407
Accumulated other comprehensive income (loss), ending balance	4,054	2,124	4,054	2,124
Amounts reclassified from accumulated other comprehensive loss:
Actuarial costs (reclassified to salaries, wages, and benefits)	89	59	284	216
Prior service costs (reclassified to salaries, wages, and benefits)	(236)	(9)	(338)	(27)
Foreign currency translation related to pension and postretirement plans	297	1	567	218
Remeasurements	(1,380)		16,491
Income tax provision AOCI expense	(2,914)	0	(3,472)	0
Amounts reclassified from accumulated other comprehensive income	$ (4,144)	$ 51	$ 13,532	$ 407