Contracts With Customers Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									$ 63,767	$ 57,453
RevenueOutsideScopeofTopic606									4,723	3,111
Noninterest Income	$ 18,042	$ 16,698	$ 17,825	$ 15,925	$ 14,706	$ 15,753	$ 15,611	$ 14,492	68,490	60,564	$ 63,607
Fees and Commissions, Depositor Accounts [Domain]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									31,515	29,704
Fees and Commissions, Debit Cards [Domain]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									21,093	18,369
Fees and Commissions, Fiduciary and Trust Accounts [Domain]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									7,159	6,529
Other Non-Interest Income [Domain]
Revenue from External Customer [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									$ 4,000	$ 2,851