Other Income and Other Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
All other income and commissions:
Other service charges	$ 20,986	$ 15,122	$ 12,532
ATM and interchange fees	16,539	13,354	12,425
Deferred compensation	11,223	(3,224)	6,322
Mortgage banking	10,055	10,587	4,649
Dividend income	7,186	10,555	0
Letter of credit fees	5,582	5,298	4,661
Electronic banking fees	4,927	5,134	5,082
Insurance commissions	2,125	2,096	2,514
Gain/(loss) on extinguishment of debt	58	(15)	(14,329)
Other	32,277	16,902	10,061
Total	110,958	75,809	43,917
All other expense:
Travel and entertainment	12,119	16,442	11,462
Other insurance and taxes	10,179	9,684	9,686
Customer relations	9,098	5,583	5,750
Supplies	6,918	6,917	4,106
Employee training and dues	5,141	7,218	5,551
Miscellaneous loan costs	4,128	3,732	2,751
Litigation and regulatory matters	2,923	644	40,517
Non-service components of net periodic pension and post-retirement cost	2,304	5,251	2,144
Tax credit investments	1,809	4,712	3,468
OREO	1,479	2,630	1,006
Repurchase and foreclosure provision/(provision credit)	(1,007)	(1,039)	(22,527)
Other	71,039	73,223	48,693
Total	$ 126,130	$ 134,997	$ 112,607