CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets
Cash and due from banks	$ 347,592	$ 360,375
Interest-bearing deposits in other banks	1,507,630	333,642
Investment securities, at fair value (amortized cost: $5,025,433 as of June 30, 2020 and $4,080,663 as of December 31, 2019)	5,135,775	4,075,644
Loans held for sale	6,698	904
Loans and leases	13,764,030	13,211,650
Less: allowance for credit losses	192,120	130,530
Net loans and leases	13,571,910	13,081,120
Premises and equipment, net	322,919	316,885
Other real estate owned and repossessed personal property	446	319
Accrued interest receivable	58,420	45,239
Bank-owned life insurance	458,720	453,873
Goodwill	995,492	995,492
Mortgage servicing rights	11,595	12,668
Other assets	576,518	490,573
Total assets	22,993,715	20,166,734
Deposits:
Interest-bearing	12,481,543	10,564,922
Noninterest-bearing	6,880,091	5,880,072
Total deposits	19,361,634	16,444,994
Short-term borrowings	200,000	400,000
Long-term borrowings	200,019	200,019
Retirement benefits payable	138,624	138,222
Other liabilities	391,541	343,241
Total liabilities	20,291,818	17,526,476
Stockholders' equity
Common stock ($0.01 par value; authorized 300,000,000 shares; issued/outstanding: 140,140,542 / 129,866,898 as of June 30, 2020; issued/outstanding: 139,917,150 / 129,928,479 as of December 31, 2019)	1,401	1,399
Additional paid-in capital	2,509,271	2,503,677
Retained earnings	415,296	437,072
Accumulated other comprehensive income (loss), net	52,731	(31,749)
Treasury stock (10,273,644 shares as of June 30, 2020 and 9,988,671 shares as of December 31, 2019)	(276,802)	(270,141)
Total stockholders' equity	2,701,897	2,640,258
Total liabilities and stockholders' equity	$ 22,993,715	$ 20,166,734