Income Taxes (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Summary of movement in uncertain tax positions
Uncertain tax positions - Beginning	$ 36,097	$ 36,887	$ 32,901
Gross increase - tax position in prior periods	679	1,493	2,411
Gross decrease - tax position in prior periods	(19,077)	(288)	(165)
Gross increase - current period tax position	17
Settlements	(2,201)	(125)
Lapse in statute of limitations	(541)	(756)	(1,227)
Foreign exchange	(116)	(1,114)	2,967
Uncertain tax positions - Ending	$ 14,858	$ 36,097	$ 36,887

Unrecognized tax benefits increases (decreases) resulting from foreign exchange.

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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 decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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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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