Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Income tax benefit from release of valuation allowance	$ (2,189,000)	$ 10,651,000	$ 0
Operating loss carryforwards, federal	83,372,000
Operating loss carryforwards, state	56,400,000
Deferred tax assets, valuation allowance	7,585,000	5,396,000
Federal NOL annual utilization limit	14,100,000
Net operating losses, unrecognized excess tax benefits, federal	1,928,000
Net operating losses, unrecognized excess tax benefits, state	37,725,000
Tax benefit from stock options exercised, federal	0
Tax fenefit from stock options exercised, state	441,000
Foreign withholding taxes	4,605,000	11,890,000	7,586,000
Excess tax benefits from stock-based compensation	(1,398,000)	13,210,000	583,000
Foreign tax credits, additional paid in capital benefit	24,718,000
Foreign tax credits utilized for financial statement purposes	20,313,000
Effective Income Tax Rate Reconciliation, Percent	(27.00%)	27.00%	29.00%
Effective tax rate excluding valuation allowance	31.00%	40.00%	41.00%
Unrecognized tax benefits	2,127,000	2,127,000	85,000
unrecognized tax benefits primarily associated with state taxes	85,000
Domestic Tax Authority [Member]
Income Taxes [Line Items]
Net operating losses included in deferred tax assets	0
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Net operating losses included in deferred tax assets	441,000
Capital Loss Carryforward Related to Business Acquisition [Member] | Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 29,318,000