Noninterest Income and Noninterest Expense (Components of Other Noninterest Income and Other Noninterest Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other noninterest income:
Income from bank-owned life insurance	$ 14,946	$ 12,424	$ 11,473
Credit-related fees	11,399	11,065	11,140
Income from derivatives	12,958	5,368	5,870
Other miscellaneous income	14,635	14,929	11,387
Total other noninterest income	53,938	43,786	39,870
Other noninterest expense:
Advertising	15,251	12,334	15,031
Corporate value and franchise taxes	15,949	13,595	12,797
Entertainment and contributions	10,777	11,359	8,260
Telecommunication and postage	14,588	14,659	14,686
Printing and supplies	4,947	5,548	5,138
Travel expenses	5,278	5,338	5,043
Tax credit investment amortization	4,943	5,166	4,850
Other retirement expense	(16,561)	(18,661)	(15,249)
Other miscellaneous expense	37,282	31,355	31,517
Total other noninterest expense	$ 92,454	$ 80,693	$ 82,073