Consolidated Statement of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Common Stock and Additional Paid-In Capital	Retained Earnings	Treasury Stock	AOCI, Net of Tax
Beginning balance at Dec. 31, 2018	$ 4,423,974		$ 1,789,977	$ 3,160,132	$ (467,961)	$ (58,174)
Beginning balance (in shares) at Dec. 31, 2018		144,961,363
Increase (Decrease) in Stockholders' Equity
Net income	164,024			164,024
Other comprehensive income (loss)	25,191					25,191
Warrants exercised	4,443		1,711		2,732
Warrants exercised (in shares)		180,226
Net activity of common stock pursuant to various stock compensation plans and agreements	(6,600)		7,436		(14,036)
Net activity of common stock pursuant to various stock compensation plans and agreements (in shares)		359,712
Cash dividends on common stock	(33,770)			(33,770)
Ending balance at Mar. 31, 2019	4,591,930		1,799,124	3,305,054	(479,265)	(32,983)
Ending balance (in shares) at Mar. 31, 2019		145,501,301
Beginning balance at Dec. 31, 2019	5,017,617		1,826,512	3,689,377	(479,864)	(18,408)
Beginning balance (in shares) at Dec. 31, 2019		145,625,385
Increase (Decrease) in Stockholders' Equity
Net income	144,824			144,824
Other comprehensive income (loss)	25,289					25,289
Net activity of common stock pursuant to various stock compensation plans and agreements	(337)		7,272		(7,609)
Net activity of common stock pursuant to various stock compensation plans and agreements (in shares)		281,396
Repurchase of common stock pursuant to the Stock Repurchase Program	(145,966)				(145,966)
Repurchase of common stock pursuant to the Stock Repurchase Program (in shares)		(4,471,682)
Cash dividends on common stock	(40,475)			(40,475)
Ending balance at Mar. 31, 2020	$ 4,902,985		$ 1,833,784	$ 3,695,759	$ (633,439)	$ 6,881
Ending balance (in shares) at Mar. 31, 2020		141,435,099