Fair Value of Financial Instruments - Summary of Information about Significant Unobservable Inputs Utilized in Company's Nonrecurring Level 3 Fair Value Measurements (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	$ 1,291,926	$ 1,109,217
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	1,291,926	1,109,217
Fair Value, Measurements, Nonrecurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	814	87
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	$ 814	$ 87
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Income approach - income capitalization | Capitalization rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs	0.120
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Minimum | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs	0.02
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Maximum | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs	0.17
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Weighted Average | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs	0.087
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Weighted Average | Income approach - income capitalization | Capitalization rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs	0.120
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Significant Unobservable Inputs (Level 3) | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	$ 419
Fair Value, Measurements, Nonrecurring | SBA loans—real estate | Significant Unobservable Inputs (Level 3) | Income approach - income capitalization | Capitalization rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans	$ 395
Fair Value, Measurements, Nonrecurring | SBA loans—non-real estate | Minimum | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs		(0.035)
Fair Value, Measurements, Nonrecurring | SBA loans—non-real estate | Maximum | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs		0.071
Fair Value, Measurements, Nonrecurring | SBA loans—non-real estate | Weighted Average | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Measurements Inputs		0.029
Fair Value, Measurements, Nonrecurring | SBA loans—non-real estate | Significant Unobservable Inputs (Level 3) | Market approach | Market data comparison
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impaired loans		$ 25