Summary of Significant Accounting Policies (Details) $ in Thousands		9 Months Ended
	Jan. 01, 2020 USD ($)	Sep. 30, 2020 USD ($) segment	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | segment		1
Operating lease, right-of-use asset		$ 2,910		$ 3,200
Estimated allowance for credit losses (ACL)		37,060	$ 37,620	$ 33,760	$ 35,570	$ 35,650		$ 37,810
Cumulative Effective, Period Of Adoption, Estimated Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated overall increase in Allowance for Credit Losses (ACL) for loans	$ 3,500
Anticipated unfunded commitments liability	$ 1,450
Cumulative Effective, Period Of Adoption, Estimated Finalized Adjustment [Member] | Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Anticipated unfunded commitments liability		4,000
Estimated allowance for credit losses (ACL)		41,000
Cumulative Effective, Period Of Adoption, Estimated Finalized Adjustment [Member] | Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Anticipated unfunded commitments liability		5,000
Estimated allowance for credit losses (ACL)		$ 44,000
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Additional operating liabilities							$ 3,580
Operating lease, right-of-use asset							$ 3,580