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Fair Value Accounting and Measurement (Financial Assets Accounted For Fair Value On Nonrecurring Basis) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | $ (161) | $ 0 | $ (306) |
Fair Value, Nonrecurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Collateral dependent loans, Fair Value | 1,845 | 11,899 | 1,845 | $ 11,899
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Collateral dependent loans, Fair Value | 0 | 0 | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Collateral dependent loans, Fair Value | 0 | 0 | 0 | 0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Collateral dependent loans, Fair Value | 1,845 | 11,899 | 1,845 | 11,899
Collateral dependent loans [Domain] | Fair Value, Nonrecurring [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | $ (958) | $ (153) | $ (958) | $ 4,941

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14172-108612 + Details
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