Consolidated Statements of Financial Position - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Cash and cash equivalents:
Cash and cash due from banks	$ 206,372	$ 228,527
Interest-bearing deposits with the Federal Reserve Bank and other banks and federal funds sold	311,204	267,312
Total cash and cash equivalents	517,576	495,839
Investment securities:
Carried at fair value	3,301,054	3,021,832
Held-to-maturity, at amortized cost (fair value of $627,615 and $618,672, respectively)	622,519	624,099
Total investment securities	3,923,573	3,645,931
Loans held-for-sale, at fair value	23,535	85,030
Loans	15,324,048	15,269,779
Allowance for loan losses	(110,284)	(109,984)
Net loans	15,213,764	15,159,795
Premises and equipment	122,452	123,442
Loan servicing rights, at fair value	64,701	71,013
Goodwill	1,134,568	1,134,568
Core deposit intangibles	27,195	28,556
Interest receivable and other assets	772,949	754,167
Total assets	21,800,313	21,498,341
Deposits:
Noninterest-bearing	3,835,427	3,809,252
Interest-bearing	12,226,572	11,784,030
Total deposits	16,061,999	15,593,282
Collateralized customer deposits	413,199	382,687
Short-term borrowings	1,740,000	2,035,000
Long-term borrowings	426,035	426,002
Interest payable and other liabilities	261,571	225,110
Total liabilities	18,902,804	18,662,081
Shareholders' equity
Preferred stock, none issued	0	0
Common stock issued	71,551	71,460
Additional paid-in capital	2,209,860	2,209,761
Retained earnings	654,605	616,149
Accumulated other comprehensive loss	(38,507)	(61,110)
Total shareholders' equity	2,897,509	2,836,260
Total liabilities and shareholders' equity	$ 21,800,313	$ 21,498,341