Income Tax Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Net interest and penalties expense	$ 301	$ 424
Accrued interest	2,516		$ 2,127
Accrued penalties	1,653		1,758
Unrecognized tax benefits related to uncertain tax positions	113,543		112,558
The amount of unrecognized tax benefits that, if recognized, would affect our effective tax rate	$ 112,228		$ 111,224