Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 283,135	$ 367,084
Interest-bearing deposits in other banks	409,357	667,560
Investment securities	5,076,766	5,234,658
Loans held for sale	397	556
Loans and leases	12,464,165	12,277,369
Less: allowance for loan and lease losses	138,574	137,253
Net loans and leases	12,325,591	12,140,116
Premises and equipment, net	288,565	289,215
Other real estate owned and repossessed personal property		329
Accrued interest receivable	47,499	47,987
Bank-owned life insurance	440,054	438,010
Goodwill	995,492	995,492
Mortgage servicing rights	18,659	13,196
Other assets	357,427	355,258
Total assets	20,242,942	20,549,461
Deposits:
Interest-bearing	11,312,288	11,485,269
Noninterest-bearing	6,050,134	6,126,853
Total deposits	17,362,422	17,612,122
Long-term debt	34	34
Retirement benefits payable	134,684	134,218
Other liabilities	224,940	270,536
Total liabilities	17,722,080	18,016,910
Commitments and contingent liabilities (Note 12)
Stockholders' equity
Common stock ($0.01 par value; authorized 300,000,000 shares; issued/outstanding: 139,611,795 / 139,601,123 as of March 31, 2018; issued/outstanding: 139,599,454 / 139,588,782 as of December 31, 2017)	1,396	1,396
Additional paid-in capital	2,490,910	2,488,643
Retained earnings	193,522	139,177
Accumulated other comprehensive loss, net	(164,684)	(96,383)
Treasury stock (10,672 shares as of both March 31, 2018 and December 31, 2017)	(282)	(282)
Total stockholders' equity	2,520,862	2,532,551
Total liabilities and stockholders' equity	$ 20,242,942	$ 20,549,461