Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Retained earnings which is available to distribute in the form of cash dividends to the Holding Company	$ 74.0
Purchase of treasury shares (in shares)	436,619	142,405
Treasury Stock Acquired, Average Cost Per Share	$ 22.88	$ 16.45
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	848,187
Savings Bank [Member]
Liquidation Account, Conversion From Mutual to Stock Form	$ 0.4	$ 0.4

Amount held in the liquidation account due to the conversion from mutual to stock form.

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- Definition

A segregation of retained earnings which is available to distribute in the form of cash dividends to the holding company.

+ References

No definition available.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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