Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Summary of Significant Accounting Policies - Impact of ASC 326 (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	$ 7,880,255				$ 7,545,748
Allowance for credit losses on loans	(110,215)	$ (108,796)			(73,658)	$ (73,720)	$ (72,086)	$ (69,944)
Liabilities: Reserve for Unfunded Commitments	(5,092)				0
Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	1,524,613				1,545,906
Allowance for credit losses on loans	(27,224)	(28,078)			(18,832)	(18,169)	(18,136)	(15,857)
Income producing - commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	3,724,839				3,702,747
Allowance for credit losses on loans	(55,440)	(51,863)			(29,265)	(28,527)	(27,010)	(28,034)
Owner occupied - Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	997,645				985,409
Allowance for credit losses on loans	(13,090)	(12,341)			(5,838)	(5,598)	(5,756)	(6,242)
Real estate mortgage residential
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	82,385				104,221
Allowance for credit losses on loans	(1,871)	(1,550)			(1,557)	(1,352)	(1,355)	(965)
Construction - commercial and residential
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	879,144				1,125,244
Allowance for credit losses on loans	(11,541)	(13,808)			(17,485)	(19,272)	(19,006)	(18,175)
Construction - commercial and residential \| C & I Owner Occupied
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	140,357				89,490
Home equity
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	72,648				80,061
Allowance for credit losses on loans	(1,007)	(1,112)			(656)	(575)	(581)	(599)
Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	2,509				2,160
Allowance for credit losses on loans	$ (42)	$ (44)			$ (25)	$ (227)	$ (242)	$ (72)
ASU 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liabilities: Reserve for Unfunded Commitments			$ (4,100)
ASU 2016-13 \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Liabilities: Reserve for Unfunded Commitments				$ (4,100)