Derivative Financial Instruments - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Derivatives Fair Value [Line Items]
Interest Rate Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net	$ 135,700,000	$ 17,000,000.0
Notional Amount of Interest Rate Derivative Instruments Not Designated as Hedging Instruments	265,000,000.0	34,400,000
Mortgage banking income	2,200,000
Difference part of merger consideration	806,000
Time deposits	1,122,430,000
Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Notional Amount of Interest Rate Derivative Instruments Not Designated as Hedging Instruments	87,800,000
Difference in fair value of asset and liability	166,000,000
Noninterest income expense	80,000,000
Equity Linked Time Deposit [Member]
Derivatives Fair Value [Line Items]
Time deposits	5,700,000
Written option at fair value	56,000
Purchased option at fair value	56,000
Other Assets [Member] | Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Fair value of derivative assets	1,900,000	0
Other Liabilities [Member] | Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Fair value of derivative liabilities	$ 2,000,000.0	$ 0