Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Cash and due from banks	$ 382,598	$ 335,419
Interest bearing cash and temporary investments	980,158	287,218
Total cash and cash equivalents	1,362,756	622,637
Investment securities
Equity and other, at fair value	80,165	61,841
Available for sale, at fair value	2,814,682	2,977,108
Held to maturity, at amortized cost	3,260	3,606
Loans held for sale, at fair value	513,431	166,461
Loans and leases	21,195,684	20,422,666
Allowance for loan and lease losses	(157,629)	(144,871)
Net loans and leases	21,038,055	20,277,795
Restricted equity securities	46,463	40,268
Premises and equipment, net	201,460	227,423
Operating lease right-of-use assets	110,718	0
Goodwill	1,787,651	1,787,651
Other intangible assets, net	18,346	23,964
Residential mortgage servicing rights, at fair value	115,010	169,025
Bank owned life insurance	320,611	313,626
Other assets	434,201	268,376
Total assets	28,846,809	26,939,781
Deposits, Interest-bearing and Noninterest-bearing, Alternative [Abstract]
Noninterest bearing	6,913,375	6,667,467
Interest bearing	15,568,129	14,470,019
Total deposits	22,481,504	21,137,486
Securities sold under agreements to repurchase	311,308	297,151
Borrowings	906,635	751,788
Junior subordinated debentures, at fair value	274,812	300,870
Junior subordinated debentures, at amortized cost	88,496	88,724
Operating lease liabilities	119,429	0
Deferred tax liability, net	52,928	25,846
Other liabilities	297,782	281,474
Total liabilities	24,532,894	22,883,339
COMMITMENTS AND CONTINGENCIES (NOTE 18)
SHAREHOLDERS' EQUITY
Common Stock, Value, Issued	3,514,000	3,512,874
Retained earnings	770,366	602,482
Accumulated other comprehensive income (loss)	29,549	(58,914)
Total shareholders' equity	4,313,915	4,056,442
Total liabilities and shareholders' equity	$ 28,846,809	$ 26,939,781
Common stock, par value (in dollar per share)	$ 0	$ 0
Common Stock, Shares Authorized	400,000,000	400,000,000
Common Stock, Shares, Issued	220,229,282	220,255,039
Common Stock, Shares, Outstanding	220,229,282	220,255,039