Summary of Significant Accounting Policies (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) reporting_unit loan	Jan. 01, 2021 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Deferral period for payment deferrals		90 days
Remaining payment deferrals		$ 16,600
PPP loans originations	$ 245,000
PPP forgiveness payoffs		$ 4,000
Number of PPP loans outstanding | loan		2,676
Amount of PPP loans outstanding		$ 241,000
SBA loans held for sale		$ 6,077		$ 0
SBA loan, amortization period		25 years
Other Investments		$ 7,800		8,000
Number of reporting units | reporting_unit		3
Goodwill		$ 239,272		234,368
Allowance for credit losses		$ 52,388		$ 21,398	$ 21,039	$ 23,298
Minimum
Property, Plant and Equipment [Line Items]
Premises and equipment, useful life		2 years
Identifiable intangible assets, useful life		7 years
Maximum
Property, Plant and Equipment [Line Items]
Premises and equipment, useful life		40 years
Identifiable intangible assets, useful life		10 years
Forecast | Accounting Standards Update 2016-13 | Minimum
Property, Plant and Equipment [Line Items]
Allowance for credit losses			$ 12,000
Forecast | Accounting Standards Update 2016-13 | Minimum | Unfunded Loan Commitment
Property, Plant and Equipment [Line Items]
Reserve			6,000
Forecast | Accounting Standards Update 2016-13 | Maximum
Property, Plant and Equipment [Line Items]
Allowance for credit losses			14,000
Forecast | Accounting Standards Update 2016-13 | Maximum | Unfunded Loan Commitment
Property, Plant and Equipment [Line Items]
Reserve			$ 7,000
First Bank
Property, Plant and Equipment [Line Items]
Goodwill		$ 227,600
First Bank Insurance
Property, Plant and Equipment [Line Items]
Goodwill		7,400
SBA
Property, Plant and Equipment [Line Items]
Goodwill		$ 4,300