Income Taxes (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Contingency [Line Items]
Understatement in deferred tax asset account	$ 17,520
Additional income tax benefit resulting from correction, amount	17,520
Net overall tax benefit including accrued interest		710	25,920
Accrued and recognized tax expense (benefit)	(2,154)	957	(9,938)
Foreign tax credits	90,941	74,253
Net operating loss carryforwards	183,866
Alternative minimum tax credits	64,088	21,438
Tax benefits related to share-based compensation	2	(11)
2003 And 2004 IRS Audit [Member]
Income Tax Contingency [Line Items]
Net overall tax benefit including accrued interest			12,356
Accrued and recognized tax expense (benefit)			10,591
2007 and 2008 IRS Audit [Member]
Income Tax Contingency [Line Items]
Additional income tax benefit resulting from correction, amount	12,747
IRS audit, interest paid	1,702
IRS audit, additional income tax benefit	354
IRS audit, decrease in reserve for uncertain tax positions	(31,912)
IRS audit, decrease in reserve for uncertain tax positions, interest related	2,154
IRS audit, income tax benefit	$ 34,067