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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, 2021 | Sep. 30, 2020
Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | $ 2,894 | $ 0
Total net (losses) gains for the period included in OCI | 9 | (36)
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 5,101 | 2,890
Transfers out of Level 3 | 0 | 0
Fair value, September 30 | 8,004 | 2,854
Period change unrealized losses in earnings for assets held at period end | 0 | 0
Period change unrealized gains in OCI for assets held at period end | 9 | (36)
Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 70,700 | 17,051
Total net (losses) gains for the period included in OCI | 2,607 | (2,415)
Purchases | 43,833 | 19,002
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (210) | (138)
Transfers into Level 3 | 981 | 4,592
Transfers out of Level 3 | (7,454) | 0
Fair value, September 30 | 110,286 | 37,636
Period change unrealized losses in earnings for assets held at period end | (185) | (456)
Period change unrealized gains in OCI for assets held at period end | 2,607 | (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 | 56,375 | 17,034
Total net (losses) gains for the period included in OCI | 206 | 732
Purchases | 19,041 | 11,751
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (1,750) | (1,030)
Transfers into Level 3 | 3,226 | 26,401
Transfers out of Level 3 | (14,643) | (9,924)
Fair value, September 30 | 62,429 | 44,720
Period change unrealized losses in earnings for assets held at period end | (35) | (247)
Period change unrealized gains in OCI for assets held at period end | 206 | 732
Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 129,969 | 34,085
Total net (losses) gains for the period included in OCI | 2,822 | (1,719)
Purchases | 62,874 | 30,753
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (1,960) | (1,168)
Transfers into Level 3 | 9,308 | 33,883
Transfers out of Level 3 | (22,097) | (9,924)
Fair value, September 30 | 180,719 | 85,210
Period change unrealized losses in earnings for assets held at period end | (220) | (703)
Period change unrealized gains in OCI for assets held at period end | 2,822 | (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 | 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 | (185) | (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 | (35) | (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 | (220) | (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 | 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 | 14 | 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 | 9 | 3
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 | $ 23 | $ 3

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