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Fair Value Measurements (Summarize Changes in Level 3 Assets) (Details) - USD ($) | 6 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021 | Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, impairments |  | $ 0 |  |
Securities transferred into or out of level 3, net | $ 0 |  |  |
Level 3 |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 20,590,000 | 19,546,000 |  |
Assets, earnings | (4,743,000) | 613,000 |  |
Assets, other comprehensive income | 0 | 0 |  |
Impairment of Intangible Assets (Excluding Goodwill) | 0 |  |  |
Assets, purchases | 925,000 | 2,000,000 |  |
Assets, (sales) | (925,000) | (1,569,000) |  |
Assets, maturities | 0 |  |  |
Assets. transfers out |  | 0 |  |
Securities transferred into or out of level 3, net | 0 |  |  |
Assets, ending balance | 15,847,000 |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value |  |  | $ 0 | $ 0
Liabilities, earnings | 0 | 1,000 |  |
Liabilities, other comprehensive income | 0 | 0 |  |
Liabilities, impairments | 0 | 0 |  |
Liabilities, purchases | 0 | (1,000) |  |
Liabilities, (sales) | 0 | 0 |  |
Liabilities, maturities | 0 | 0 |  |
Liabilities, transfers out | 0 | 0 |  |
Level 3 | Debt securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 0 | 1,000,000 |  |
Assets, earnings |  | 0 |  |
Assets, other comprehensive income |  | 0 |  |
Assets, impairments |  | 0 |  |
Assets, purchases |  | 0 |  |
Assets, (sales) |  | (1,000,000) |  |
Assets. transfers out |  | 0 |  |
Level 3 | Equity securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 20,590,000 | 18,546,000 |  |
Assets, earnings |  | 605,000 |  |
Assets, other comprehensive income |  | 0 |  |
Assets, impairments |  | 0 |  |
Assets, purchases |  | 2,000,000 |  |
Assets, (sales) |  | (561,000) |  |
Assets, maturities |  | 0 |  |
Assets. transfers out |  | 0 |  |
Level 3 | Common stock |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 9,294,000 | 9,215,000 |  |
Assets, earnings | (4,743,000) | 640,000 |  |
Assets, other comprehensive income | 0 | 0 |  |
Assets, impairments | 0 | 0 |  |
Assets, purchases | 0 | 0 |  |
Assets, (sales) | 0 | (561,000) |  |
Assets. transfers out | 0 | 0 |  |
Assets, ending balance | 4,551,000 |  |  |
Level 3 | Preferred stocks |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 11,296,000 | 9,331,000 |  |
Assets, earnings | 0 | (35,000) |  |
Assets, other comprehensive income | 0 | 0 |  |
Assets, impairments | 0 | 0 |  |
Assets, purchases | 925,000 | 2,000,000 |  |
Assets, (sales) | (925,000) | 0 |  |
Assets. transfers out | 0 | 0 |  |
Assets, ending balance | 11,296,000 |  |  |
Level 3 | Arbitrage trading account |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | 0 | 0 |  |
Assets, earnings |  | 8,000 |  |
Assets, other comprehensive income |  | 0 |  |
Assets, impairments |  | 0 |  |
Assets, purchases |  | 0 |  |
Assets, (sales) |  | (8,000) |  |
Level 3 | Corporate |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Assets, beginning balance | $ 0 | 1,000,000 |  |
Assets, earnings |  | 0 |  |
Assets, other comprehensive income |  | 0 |  |
Impairment of Intangible Assets (Excluding Goodwill) |  | 0 |  |
Assets, purchases |  | 0 |  |
Assets, (sales) |  | (1,000,000) |  |
Assets, maturities |  | 0 |  |
Securities transferred into or out of level 3, net |  | $ 0 |  |

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