Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of unrecognized tax benefits
Balance at January 1	$ 151,898	$ 163,859	$ 232,050
Tax positions related to current year:
Additions	19,482	10,874	10,738
Tax positions related to prior years:
Additions	29,312	1,541	54,058
Reductions	(20,156)	(800)	0
Lapses in statute of limitations	(9,580)	(14,174)	(16,374)
Settlements	0	0	(96,926)
Payments	0	(9,780)	(22,151)
Foreign exchange loss	38	378	2,464
Balance at December 31	$ 170,994	$ 151,898	$ 163,859

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Foreign exchange loss.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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