Income Taxes (Income Tax Rate Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	35.00%	35.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
United States federal tax expense (benefit) at statutory rate	$ (18,930)	$ 20,076	$ (15,550)
State taxes, net of United States federal tax benefit	(841)	(1,098)	1,320
Change in valuation allowance	25,046	2,136	(9,119)
Non-deductible stock compensation	415	341	571
Impact of non-U.S. jurisdictional tax rate difference	487	313	(368)
Research and development tax credit	(1,632)	(1,923)	(1,372)
Transfer pricing adjustment	0	0	2,426
Increase (reversal) of unrecognized tax benefits	671	(7,826)	2,100
Non-U.S. withholding tax	1,805	471	275
Other	(2,118)	28	2,388
Total income tax expense (benefit)	$ 4,903	$ 12,518	$ (17,329)