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Consolidated Statements of Financial Condition (Unaudited) (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Dec. 31, 2020
Securities held to maturity, allowance for credit losses | $ 5 | $ 5 | $ 7
Securities held to maturity, fair value | 224,164 | 224,164 | 282,035
Loans, allowance for credit losses | 45,444 | 45,444 | 52,420
Debt issuance costs | $ 1,166 | $ 1,166 | $ 1,377
Common stock, par value | $ 0.01 | $ 0.01 | $ 0.01
Common stock, shares authorized | 50,000,000 | 50,000,000 | 50,000,000
Common stock, shares issued | 16,099,556 | 16,099,556 | 16,099,556
Treasury stock, shares | 257,475 | 257,475 | 57,630
Series A 3% Preferred Stock [Member] |  |  |
Preferred stock, par value | $ 100 | $ 100 | $ 100
Preferred stock, shares authorized | 1,533 | 1,533 | 1,533
Preferred stock, shares issued | 1,435 | 1,435 | 1,435
Preferred stock, dividend percentage | 3.00% | 3.00% | 3.00%
Series B-1 8.48% Preferred Stock [Member] |  |  |
Preferred stock, par value | $ 100 | $ 100 | $ 100
Preferred stock, shares authorized | 200,000 | 200,000 | 200,000
Preferred stock, shares issued | 171,486 | 171,486 | 171,847
Preferred stock, dividend percentage | 8.48% | 8.48% | 8.48%

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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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