Revenue Recognition In-Scope and Out-of-Scope Revenue Streams (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Fees and Commissions on Trust and Fiduciary Accounts	$ 2,206	$ 2,147	$ 6,014	$ 5,275
Fees and Commissions on Depositor Accounts	4,589	4,803	13,418	13,858
Insurance and retail brokerage commissions	1,872	2,128	5,560	6,652
Fees and Commissions on Debit Cards	5,044	4,780	14,929	13,873
Derivatives mark to market	0	(14)	789	(49)
Gain on sale of other loans and assets	643	503	3,548	1,267
Other income	1,754	2,244	5,125	5,674
Noninterest Income	19,757	19,790	68,108	55,626
In-Scope of Topic 606 [Member]
Fees and Commissions on Trust and Fiduciary Accounts			6,014	5,275
Fees and Commissions on Depositor Accounts			13,418	13,858
Insurance and retail brokerage commissions			5,560	6,652
Fees and Commissions on Debit Cards			14,929	13,873
Gain on sale of other loans and assets	335	181	726	542
Other income	928	1,238	2,800	3,116
Noninterest Income	14,974	15,277	43,447	43,316
Out-Of-Scope of Topic 606 [Member]
Noninterest Income	$ 4,783	$ 4,513	$ 24,661	$ 12,310