Income Taxes (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Activity relating to the Company's unrecognized tax benefits
Balance at the beginning of the period	$ 16,387,000
Gross increases related to current period tax positions	154,000
Balance at the end of the period	16,541,000
Unrecognized tax benefits relating to state research credits	200,000
Portion of unrecognized tax benefits, if recognized would decrease the entity's tax provision and increase net income	13,600,000
Effective income tax rate (as a percent)	45.00%	36.00%
Correction of error in income tax expense recorded	900,000
Provision made for undistributed earnings of foreign subsidiaries	0
Undistributed earnings for non-U.S. subsidiaries which are deemed to be permanently reinvested	$ 27,900,000