Changes in Accumulated Other Comprehensive Income by Component (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	$ 25,944	$ (66,752)
Other comprehensive income before reclassifications to consolidated statements of income	(13,513)	(14,368)
Amounts reclassified from accumulated other comprehensive (loss) income to the consolidated statements of income	1,668	2,700
Net current-period other comprehensive income (loss)	(11,845)	(11,668)
Accumulated other comprehensive income (loss)	14,099	(78,420)
Gains and Losses on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(519)	(432)
Other comprehensive income before reclassifications to consolidated statements of income	(146)	525
Amounts reclassified from accumulated other comprehensive (loss) income to the consolidated statements of income	119	(98)
Net current-period other comprehensive income (loss)	(27)	427
Accumulated other comprehensive income (loss)	(546)	(5)
Pension and Other Postretirement Benefit Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	(73,273)	(146,441)
Other comprehensive income before reclassifications to consolidated statements of income	(7,419)	(388)
Amounts reclassified from accumulated other comprehensive (loss) income to the consolidated statements of income	1,549	2,798
Net current-period other comprehensive income (loss)	(5,870)	2,410
Accumulated other comprehensive income (loss)	(79,143)	(144,031)
Foreign Currency Items
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Accumulated other comprehensive income (loss)	99,736	80,121
Other comprehensive income before reclassifications to consolidated statements of income	(5,948)	(14,505)
Amounts reclassified from accumulated other comprehensive (loss) income to the consolidated statements of income	0	0
Net current-period other comprehensive income (loss)	(5,948)	(14,505)
Accumulated other comprehensive income (loss)	$ 93,788	$ 65,616