Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Employee benefit accruals	$ 16,201	$ 11,678
Impairment of investments	4,332	0
Impact of timing of settlement payments	39,840	33,485
Various U.S. state tax loss carryforwards	6,713	8,339
Other	0	0
Deferred tax assets	67,086	53,502
Less: Valuation allowance	(3,900)	(4,933)
Net deferred tax assets	63,186	48,569
Deferred tax liabilities:
Excess of tax basis over book-basis non-consolidated entities	(7,292)	(6,190)
Book/tax differences on fixed and Intangible assets	(52,598)	(52,972)
Deferred Tax Liabilities, Deferred Expense, Capitalized Interest	(4,080)	0
Book/tax differences on inventory	(16,891)	(20,062)
Book/tax differences on long-term investments	(29,701)	(32,756)
Impact of accounting on convertible debt	(30,494)	(31,033)
Other	(1,559)	(1,460)
Deferred tax liabilities	(142,615)	(144,473)
Net deferred tax liabilities	$ (79,429)	$ (95,904)