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Significant Accounting Policies - Investment in Marketable Securities (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) marketableSecurity
Real Estate [Line Items] |  |  |  |
Allowance for loan loss | $ 0 | $ 0 | $ 0 |
Proceeds from sale of marketable securities | 0 | 0 | $ 7,800,000 |
Number of marketable securities sold | security |  |  | 1 |
Proceeds from the repayment of debt marketable securities |  |  | $ 3,700,000 |
Number of securities repaid | security |  |  | 1 |
Equity marketable securities | 0 | 0 |  |
Number of securities sold | marketableSecurity |  |  |  | 1
Proceeds from sale of equity marketable securities |  |  |  | $ 4,200,000
Marketable securities, realized loss |  |  | $ 6,500,000 |
Commercial mortgage-backed securities - available-for-sale |  |  |  |
Real Estate [Line Items] |  |  |  |
Cost basis of commercial mortgage backed securities | $ 18,300,000 | 11,500,000 |  |
Number of securities in unrealized gain position | security | 1 |  |  |
Unrealized gain | $ 200,000 |  |  |
Fair market value | $ 5,500,000 |  |  |
Debt securities, available-for-sale, continuous unrealized loss position, less than 12 months, number of positions | security | 2 |  |  |
Unrealized loss | $ 1,500,000 | 1,900,000 |  |
Fair value of security in a continuous unrealized loss position for less than 12 months | $ 11,800,000 | 9,600,000 |  |
Debt securities, available-for-sale, continuous unrealized loss position, 12 months or longer, number of positions | security | 1 |  |  |
Debt securities, held-to-maturity, amortized cost, after allowance for credit loss | $ 5,489,000 | $ 0 |  |
Debt securities, held-to-maturity, amortized cost, discount | $ 200,000 |  |  |

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