Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended		1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Mar. 31, 2011 Notices of proposed adjustments (NOPA)
Income Taxes
Expected future taxable income to fully realize the deferred tax assets	$ 73,863
Change in net deferred tax assets attributable to other comprehensive income	448
Domestic taxable income	141,368	194,228
Unremitted earnings of non-US subsidiaries	186,000
Non-US subsidiary cash and cash equivalents	43,000
Percentage of pre-tax earnings from a country which does not impose a corporate income tax	28.00%
Minimum percentage used to measure tax benefit of uncertain tax position	50.00%
Reconciliation of the beginning and ending amounts of total unrecognized tax benefits
Balance at the beginning of the period	5,506	5,011
Gross increase related to current year tax positions		2,235
Settlements		(1,740)
Gross decrease related to prior years' tax positions	(2,235)
Balance at the end of the period	3,271	5,506
Portion of unrecognized tax benefits that, if recognized, would affect the effective tax rate	3,175
Portion of unrecognized tax benefits that, if recognized, would be recorded as an adjustment to long term deferred tax assets	96
Interest expenses on income tax contingencies	83
Accrued interest on income tax contingencies	817	734
Income Taxes
Aggregate additional taxable income related to transfer pricing arrangements			55,000
Additional federal taxes and penalties, excluding interest			$ 27,000