Condensed Financial Information (Parent Company Only) - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Provision for income taxes	$ 50,358	$ 61,983	$ 46,624
NET INCOME	215,713	92,940	96,814
Preferred stock dividends	0	0	24
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	215,713	92,940	96,790
Parent Company
Income Statement [Abstract]
Dividends from subsidiaries	145,980	69,107	83,710
Other income	658	4,111	2,465
Income	146,638	73,218	86,175
EXPENSE	32,714	32,234	21,990
Income before income taxes and equity in undistributed net income of subsidiaries	113,924	40,984	64,185
Provision for income taxes	(10,732)	(12,311)	(7,557)
Income before equity in undistributed net income of subsidiaries	124,656	53,295	71,742
Equity in undistributed net income of subsidiaries	91,057	39,645	25,072
NET INCOME	215,713	92,940	96,814
Preferred stock dividends	0	0	24
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS	$ 215,713	$ 92,940	$ 96,790