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Fair Value Measurements (Change in Fair Value of Securities Using Level 3 Inputs) (Details) - Available-for-sale Securities [Member] - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2020 | Sep. 30, 2019
Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31, | $ 0 |
Total net (losses) gains for the period included in OCI | (36) |
Purchases | 0 |
Sales | 0 |
Issuances | 0 |
Settlements | 0 |
Transfers into Level 3 | 2,890 |
Transfers out of Level 3 | 0 |
Fair value, September 30 | 2,854 |
Period change unrealized (losses) gains in earnings for assets held at period end | 0 |
Period change unrealized gains (losses) in OCI for assets held at period end | (36) |
Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31, | 17,051 | $ 0
Total net (losses) gains for the period included in OCI | (2,415) | (69)
Purchases | 19,002 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (138) | 0
Transfers into Level 3 | 4,592 | 16,419
Transfers out of Level 3 | 0 | 0
Fair value, September 30 | 37,636 | 16,350
Period change unrealized (losses) gains in earnings for assets held at period end | (456) | 0
Period change unrealized gains (losses) in OCI for assets held at period end | (2,415) |
Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31, | 17,034 | 7,409
Total net (losses) gains for the period included in OCI | 732 | (14)
Purchases | 11,751 | 18,404
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (1,030) | (105)
Transfers into Level 3 | 26,401 | 13,603
Transfers out of Level 3 | (9,924) | (19,662)
Fair value, September 30 | 44,720 | 19,879
Period change unrealized (losses) gains in earnings for assets held at period end | (247) | 0
Period change unrealized gains (losses) in OCI for assets held at period end | 732 |
Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31, | 34,085 | 7,409
Total net (losses) gains for the period included in OCI | (1,719) | (83)
Purchases | 30,753 | 18,404
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (1,168) | (105)
Transfers into Level 3 | 33,883 | 30,022
Transfers out of Level 3 | (9,924) | (19,662)
Fair value, September 30 | 85,210 | 36,229
Period change unrealized (losses) gains in earnings for assets held at period end | (703) | 0
Period change unrealized gains (losses) in OCI for assets held at period end | (1,719) |
Gain (Loss) on Investments [Member] | Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | 0 |
Gain (Loss) on Investments [Member] | Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | (456) |
Gain (Loss) on Investments [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | (247) |
Gain (Loss) on Investments [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | (703) |
Net Investment Income Earned [Member] | Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | 0 |
Net Investment Income Earned [Member] | Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | 0 | 0
Net Investment Income Earned [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | 3 | 244
Net Investment Income Earned [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains for the period included in net income | $ 3 | $ 244

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