Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning	$ 9,568,000	$ (406,000)	$ (7,494,000)
Other comprehensive income (loss) before reclassifications	(36,633,000)	11,156,000	4,472,000
Income tax	2,671,000	(2,008,000)	1,931,000
Other comprehensive income (loss) before reclassifications, net of tax	(33,962,000)	9,148,000	6,403,000
Amounts reclassified from accumulated other comprehensive income (loss)	631,000	1,326,000	1,123,000
Income tax	(238,000)	(500,000)	(438,000)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	393,000	826,000	685,000
Other comprehensive income (loss)	(33,569,000)	9,974,000	7,088,000
Accumulated other comprehensive income (loss), ending	(24,001,000)	9,568,000	(406,000)
Reclassified actuarial net losses	(800,000)	(1,400,000)	(1,000,000)
Reclassified prior service cost			200,000
Retirement Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning	(6,479,000)	(10,318,000)	(7,707,000)
Other comprehensive income (loss) before reclassifications	(7,021,000)	4,902,000	(5,487,000)
Income tax	2,671,000	(1,897,000)	2,141,000
Other comprehensive income (loss) before reclassifications, net of tax	(4,350,000)	3,005,000	(3,346,000)
Amounts reclassified from accumulated other comprehensive income (loss)	816,000	1,366,000	1,205,000
Income tax	(310,000)	(532,000)	(470,000)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	506,000	834,000	735,000
Other comprehensive income (loss)	(3,844,000)	3,839,000	(2,611,000)
Accumulated other comprehensive income (loss), ending	(10,323,000)	(6,479,000)	(10,318,000)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning	15,892,000	9,749,000	0
Other comprehensive income (loss) before reclassifications	(29,539,000)	6,254,000	9,959,000
Income tax	0	(111,000)	(210,000)
Other comprehensive income (loss) before reclassifications, net of tax	(29,539,000)	6,143,000	9,749,000
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0
Income tax	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	0	0	0
Other comprehensive income (loss)	(29,539,000)	6,143,000	9,749,000
Accumulated other comprehensive income (loss), ending	(13,647,000)	15,892,000	9,749,000
Other
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), beginning	155,000	163,000	213,000
Other comprehensive income (loss) before reclassifications	(73,000)	0	0
Income tax	0	0	0
Other comprehensive income (loss) before reclassifications, net of tax	(73,000)	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	(185,000)	(40,000)	(82,000)
Income tax	72,000	32,000	32,000
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(113,000)	(8,000)	(50,000)
Other comprehensive income (loss)	(186,000)	(8,000)	(50,000)
Accumulated other comprehensive income (loss), ending	$ (31,000)	$ 155,000	$ 163,000