Accumulated Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016		Jun. 30, 2015		Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance				$ (88,458)		$ (65,094)
Other comprehensive income (loss) before reclassifications				5,197		(19,410)
Amounts reclassified from accumulated other comprehensive income (loss)				82	[1]	625	[2]
Other comprehensive income (loss)		$ (5,688)	$ 8,709	5,279		(18,785)
Ending balance		(83,179)	(83,879)	(83,179)		(83,879)
AOCI, Pension and other postretirement benefit plans, tax		9,840	11,657	9,840		11,657		$ 9,879	$ 11,952
AOCI, Cumulative changes in net gain (loss) from cash flow hedges, tax		0	33	0		33		$ 5	$ 50
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance				(41,365)		(14,193)
Other comprehensive income (loss) before reclassifications				5,197		(19,250)
Amounts reclassified from accumulated other comprehensive income (loss)				0	[1]	0	[2]
Other comprehensive income (loss)				5,197		(19,250)
Ending balance		(36,168)	(33,443)	(36,168)		(33,443)
Funded status of pension plans and other postretirement benefits
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[3]			(47,082)		(50,808)
Other comprehensive income (loss) before reclassifications	[3]			0		0
Amounts reclassified from accumulated other comprehensive income (loss)	[3]			71	[1]	531	[2]
Other comprehensive income (loss)	[3]			71		531
Ending balance	[3]	(47,011)	(50,277)	(47,011)		(50,277)
Reclassification from AOCI, Current Period, Tax				286		38
Unrealized gain (loss) on derivative instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[4]			(11)		(93)
Other comprehensive income (loss) before reclassifications	[4]					(160)
Amounts reclassified from accumulated other comprehensive income (loss)	[4]			11	[1]	94	[2]
Other comprehensive income (loss)	[4]			11		(66)
Ending balance	[4]	$ 0	$ (159)	0		(159)
Reclassification from AOCI, Current Period, Tax				$ 50		$ 6

[1] Net of taxes of $38 and $6 for the pension plans and postretirement benefits and unrealized gain (loss) on derivatives, respectively.

[2] Net of taxes of $286 and $50 for the pension plans and postretirement benefits and unrealized gain (loss) on derivatives, respectively.

[3] Net of taxes of $11,657 and $11,952 as of June 30, 2015 and December 31, 2014, respectively.

[4] Net of taxes of $0 and $5 as of June 30, 2016 and December 31, 2015, respectively. Net of taxes of $33 and $50 as of June 30, 2015 and December 31, 2014, respectively.