Accumulated Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017		Mar. 31, 2016		Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, Beginning of Period		$ 635,786
Other comprehensive income (loss) before reclassifications		4,024		$ 10,930
Amounts reclassified from accumulated other comprehensive income (loss)		30		37
Other comprehensive income (loss)		4,054		10,967
Balance, End of Period		679,239
AOCI, Pension and other postretirement benefit plans, tax		9,144		9,860		$ 9,160	$ 9,879
AOCI, Cumulative changes in net gain (loss) from cash flow hedges, tax		65		3		$ 0	$ 5
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, Beginning of Period		(46,446)		(41,365)
Other comprehensive income (loss) before reclassifications		4,138		10,926
Amounts reclassified from accumulated other comprehensive income (loss)		0	[1]	0	[2]
Other comprehensive income (loss)		4,138		10,926
Balance, End of Period		(42,308)		(30,439)
Funded status of pension plans and other postretirement benefits
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, Beginning of Period	[3]	(45,816)		(47,082)
Other comprehensive income (loss) before reclassifications	[3]	0		0
Amounts reclassified from accumulated other comprehensive income (loss)		30		35	[2],[3]
Other comprehensive income (loss)		30		35
Balance, End of Period		(45,786)		(47,047)	[3]
Reclassification from AOCI, Current Period, Tax		19		14
Unrealized gain (loss) on derivative instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, Beginning of Period	[4]	0		(11)
Other comprehensive income (loss) before reclassifications		(114)		4	[4]
Amounts reclassified from accumulated other comprehensive income (loss)	[4]	0	[1]	2	[2]
Other comprehensive income (loss)		(114)		6
Balance, End of Period		(114)		(5)	[4]
Reclassification from AOCI, Current Period, Tax		1
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, Beginning of Period		(92,262)		(88,458)
Other comprehensive income (loss)		4,054
Balance, End of Period		$ (88,208)		$ (77,491)

[1] Net of taxes of $14 for the pension plans and postretirement benefits

[2] Net of taxes of $19 and $1 for the pension plans and postretirement benefits and unrealized gain (loss) on derivatives, respectively.

[3] Net of taxes of $9,144 and $9,160 as of March 31, 2017 and December 31, 2016, respectively. Net of taxes of $9,860 and $9,879 as of March 31, 2016 and December 31, 2015, respectively.

[4] Net of taxes of $65 and $0 as of March 31, 2017 and December 31, 2016, respectively. Net of taxes of $3 and $5 as of March 31, 2016 and December 31, 2015, respectively.