Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
ASSETS
Cash and due from banks	$ 335,419	$ 330,856
Interest bearing cash and temporary investments	287,218	303,424
Total cash and cash equivalents	622,637	634,280
Investment securities
Equity and other, at fair value	61,841	12,255
Available for sale, at fair value	2,977,108	3,065,769
Held to maturity, at amortized cost	3,606	3,803
Loans held for sale, at fair value	166,461	259,518
Loans and leases	20,422,666	19,019,192
Allowance for loan and lease losses	(144,871)	(140,608)
Net loans and leases	20,277,795	18,878,584
Restricted equity securities	40,268	43,508
Premises and equipment, net	227,423	269,182
Goodwill	1,787,651	1,787,651
Other intangible assets, net	23,964	30,130
Residential mortgage servicing rights, at fair value	169,025	153,151
Other real estate owned	10,958	11,734
Bank owned life insurance	313,626	306,864
Other assets	257,418	224,018
Total assets	26,939,781	25,680,447
Deposits, Interest-bearing and Noninterest-bearing, Alternative [Abstract]
Noninterest bearing	6,667,467	6,505,628
Interest bearing	14,470,019	13,442,672
Total deposits	21,137,486	19,948,300
Securities sold under agreements to repurchase	297,151	294,299
Term debt	751,788	802,357
Junior subordinated debentures, at fair value	300,870	277,155
Junior subordinated debentures, at amortized cost	88,724	100,609
Deferred tax liability, net	25,846	21,930
Other liabilities	281,474	266,430
Total liabilities	22,883,339	21,711,080
COMMITMENTS AND CONTINGENCIES (NOTE 18)
SHAREHOLDERS' EQUITY
Common stock, no par value, shares authorized: 400,000,000 as of December 31, 2018 and 2017; issued and outstanding: 220,255,039 as of December 31, 2018 and 220,148,824 as of December 31, 2017	3,512,874	3,517,258
Retained earnings	602,482	477,101
Accumulated other comprehensive loss	(58,914)	(24,992)
Total shareholders' equity	4,056,442	3,969,367
Total liabilities and shareholders' equity	$ 26,939,781	$ 25,680,447