Income Tax Expense (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Y
Net operating loss ("NOL") carry forwards
Federal net operating loss carry forwards	$ 88,899
State net operating loss carry forwards	25,803
Foreign net operating loss carry forwards	51,971
Period for which foreign NOL can be carried forward (in years)	10
Tax credit carry forwards
Foreign tax credit carry forwards	18,239
Research and development tax credit carry forwards	9,550
Alternative minimum tax credit carry forwards	2,107
State tax credits carry forward	2,094
Other non-U.S. tax credits	$ 759