Fair Value Measurements - Fair Value Measurements - Valuation Methodology and Unobservable Inputs for Level 3 Assets Measured at Fair Value on a Nonrecurring Basis (Details) - Fair Value, Measurements, Nonrecurring $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)		Dec. 31, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 32,765		$ 102,274
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	32,111		98,114
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	654		4,160
Non Purchased Credit Impaired Loans and Leases
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	32,765	[1]	102,274	[2]
Non Purchased Credit Impaired Loans and Leases | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	32,111	[1]	98,114	[2]
Non Purchased Credit Impaired Loans and Leases | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	654	[1]	$ 4,160	[2]
Discount Rates | Discounted Cash Flow | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	26,278
No Discounts | Third party appraisals | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 5,833
Measurement Input, Discount Rate | Minimum | Discounted Cash Flow | Non Purchased Credit Impaired Loans and Leases | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rates	0.0375
Measurement Input, Discount Rate | Maximum | Discounted Cash Flow | Non Purchased Credit Impaired Loans and Leases | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rates	0.0775

[1] Includes nonaccrual loans and leases and performing TDRs with balances greater than $250,000.

[2] Includes nonaccrual loans and leases and performing TDRs with balances greater than $250,000.