Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Difference between income tax provision computed at the statutory Federal income tax rate and financial statement income tax
Provision at Federal rate of 21% for 2018, 35% for 2017 and 2016)									$ 18,267	$ 30,699	$ 35,000
State income taxes, net of Federal impact									2,985	1,850	2,662
Research and experimentation credits									(4,040)	(2,853)	(71)
Stock award vesting									(1,513)	(7,882)
Tax uncertainties									(122)	166	(1,597)
Section 199 manufacturing deduction									168	(962)	(4,060)
Section 162(m) compensation limitation									951	273	297
Foreign rate differential									1,238	162	857
Valuation allowance for deferred tax assets									(177)	2,351	1,287
Other impact of foreign operations									2,755	3,933	2,157
Statutory rate change									(87)	(2,210)
Other									432	819	585
Total income tax provision	$ 4,669	$ 4,391	$ 5,607	$ 6,190	$ 6,705	$ 8,806	$ 8,722	$ 2,113	$ 20,857	$ 26,346	$ 37,117