Income Taxes (Deferred Income Taxes Components) (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Deferred Income Tax Liabilities [Line Items]
Accrued postretirement benefits	$ 16,785,000	$ 15,408,000
Other benefit obligations	122,241,000	101,923,000
Accounts receivable	17,925,000	24,911,000
State income tax loss carryforwards	26,077,000	30,036,000
U.S. Federal income tax loss carryforwards	2,368,000	2,613,000
U.S Federal foreign income tax credit carryforwards	837,000	8,265,000
Non-U.S. income tax loss carryforwards	30,460,000	32,600,000
Other	50,134,000	61,753,000
Deferred tax assets	266,827,000us-gaap_DeferredTaxAssetsGross	277,509,000us-gaap_DeferredTaxAssetsGross
Valuation allowance	(73,656,000)	(72,767,000)
Deferred tax assets, net	193,171,000us-gaap_DeferredTaxAssetsNet	204,742,000us-gaap_DeferredTaxAssetsNet
Property, plant and equipment	139,765,000	134,627,000
Unrealized gain on available-for-sale securities	34,764,000	115,785,000
Goodwill and other intangible assets	308,954,000	293,749,000
Deferred tax liabilities	947,197,000us-gaap_DeferredIncomeTaxLiabilities	1,041,888,000us-gaap_DeferredIncomeTaxLiabilities
Deferred Income Tax Liabilities, Net	754,026,000us-gaap_DeferredTaxLiabilities	837,146,000us-gaap_DeferredTaxLiabilities
Pension Plan, Defined Benefit [Member]
Deferred Income Tax Liabilities [Line Items]
Prepaid pension cost	$ 463,714,000	$ 497,727,000

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