Investment Securities - Additional Information (Details)	12 Months Ended
Dec. 31, 2021 USD ($) Security	Dec. 31, 2020 USD ($) Security
Schedule Of Available For Sale Securities [Line Items]
Equity securities, at fair value	$ 397,000	$ 218,000
Tax rate used to calculate tax-equivalent yields (in hundredths)	21.00%
Percentage investment book value exceeds stockholders' equity (in hundredths)	10.00%
Debt securities, available-for-sale, restricted	$ 590,000,000	531,000,000
Available-for-sale, 12 months or longer, Fair Value	186,350,000	2,377,000
12 months or longer, unrealized losses	$ 4,627,000	$ 0
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies
Schedule Of Available For Sale Securities [Line Items]
Number of securities in unrealized loss positions \| Security	6	0
Available-for-sale, 12 months or longer, Fair Value	$ 139,846,000	$ 0
12 months or longer, unrealized losses	$ 2,936,000	$ 0
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions \| Security	0	0
Obligations of States and Political Subdivisions
Schedule Of Available For Sale Securities [Line Items]
Number of securities in unrealized loss positions \| Security	0	0
Available-for-sale, 12 months or longer, Fair Value	$ 0	$ 0
12 months or longer, unrealized losses	$ 0	$ 0
Mortgage-backed Securities: GSE Residential
Schedule Of Available For Sale Securities [Line Items]
Number of securities in unrealized loss positions \| Security	15	2
Available-for-sale, 12 months or longer, Fair Value	$ 46,504,000	$ 2,377,000
12 months or longer, unrealized losses	$ 1,691,000	$ 0
Other Securities
Schedule Of Available For Sale Securities [Line Items]
Number of securities in unrealized loss positions \| Security	0	0
Available-for-sale, 12 months or longer, Fair Value	$ 0	$ 0
12 months or longer, unrealized losses	$ 0	$ 0

Percentage investment book value exceeds stockholders' equity.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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