Unaudited Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Stockholders' Equity beginning balance at Dec. 31, 2018	$ 3,340,180	$ 123	$ 2,306,843	$ 3,817,656	$ (913,858)	$ (1,870,584)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	172,107			172,107
Other comprehensive loss, net of tax	(20,334)				(20,334)
Acquisition of common stock	(3,322)		33,000			(36,322)
Share-based compensation expense	12,541		12,541
Issuance of common stock	29,795		29,795
Stockholders' Equity ending balance at Mar. 31, 2019	3,530,967	123	2,382,179	3,989,763	(934,192)	(1,906,906)
Stockholders' Equity beginning balance at Dec. 31, 2019	3,711,616	124	2,494,721	4,712,729	(972,465)	(2,523,493)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	147,060			147,060
Other comprehensive loss, net of tax	(619,659)				(619,659)
Acquisition of common stock	(530,237)		75,000			(605,237)
Share-based compensation expense	14,175		14,175
Issuance of common stock	73,274	1	73,273
Stockholders' Equity ending balance at Mar. 31, 2020	2,796,229	$ 125	$ 2,657,169	$ 4,859,789	$ (1,592,124)	$ (3,128,730)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income, from currency, tax	$ 0