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Fair Value Measurements, Fair Value Measured On a Nonrecurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Real estate and other repossessed assets [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Gross charge-offs against allowance for loan losses | $ 0 | $ 0
Net losses and expenses of repossessed assets, net | (4,602) | (461)
Fair Value, Nonaccruing Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Gross charge-offs against allowance for loan losses | 39,299 | 31,305
Net losses and expenses of repossessed assets, net | 0 | 0
Fair Value, Inputs, Level 1 [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonaccruing Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Pension Plan [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Defined Benefit Plan, Plan Assets, Amount | 38,000 | 36,000
Fair Value, Inputs, Level 2 [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 18,188 | 5,986
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonaccruing Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 801 | 41
Fair Value, Inputs, Level 3 [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | 2,842 | 1,551
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonaccruing Loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets, Fair Value Disclosure | $ 20,423 | $ 55,665

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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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