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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 | 6 Months Ended
--- | ---
Jun. 30, 2022 | Jun. 30, 2021
Obligations of States and Political Subdivisions [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | $ 7,745 | $ 2,894
Total net (losses) gains for the period included in OCI | (581) | (13)
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 5,101
Transfers out of Level 3 | 0 | 0
Fair value, June 30 | 7,008 | 7,982
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | (156) | 0
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (581) | (13)
Corporate Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 114,127 | 70,700
Total net (losses) gains for the period included in OCI | (16,422) | 1,899
Purchases | 55,343 | 25,403
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (3,903) | (167)
Transfers into Level 3 | 19,214 | 0
Transfers out of Level 3 | (7,037) | (7,454)
Fair value, June 30 | 159,289 | 90,405
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | (2,047) | 11
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (16,424) | 1,899
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 | 124,909 | 56,375
Total net (losses) gains for the period included in OCI | (8,592) | 396
Purchases | 39,133 | 17,639
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (6,479) | (1,429)
Transfers into Level 3 | 0 | 3,226
Transfers out of Level 3 | (24,646) | (5,394)
Fair value, June 30 | 123,616 | 70,737
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | (777) | (82)
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (8,551) | 396
Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 251,282 | 129,969
Total net (losses) gains for the period included in OCI | (26,058) | 2,282
Purchases | 94,476 | 43,042
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (10,405) | (1,596)
Transfers into Level 3 | 19,214 | 8,327
Transfers out of Level 3 | (35,331) | (12,848)
Fair value, June 30 | 290,320 | 169,124
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | (2,987) | (71)
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (26,019) | 2,282
Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 245 |
Total net (losses) gains for the period included in OCI | (17) |
Purchases | 0 |
Sales | 0 |
Issuances | 0 |
Settlements | (11) |
Transfers into Level 3 | 0 |
Transfers out of Level 3 | (217) |
Fair value, June 30 | 0 |
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | 0 |
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (17) |
Commercial Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair value, December 31 | 4,256 |
Total net (losses) gains for the period included in OCI | (446) |
Purchases | 0 |
Sales | 0 |
Issuances | 0 |
Settlements | (12) |
Transfers into Level 3 | 0 |
Transfers out of Level 3 | (3,431) |
Fair value, June 30 | 407 |
Change in unrealized losses (gains) for the period included in earnings for assets held at period end | (7) |
Change in unrealized losses (gains) for the period included in OCI for assets held at period end | (446) |
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 in the period included in net realized and unrealized (losses) gains | (156) | 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 in the period included in net realized and unrealized (losses) gains | (2,047) | 11
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 in the period included in net realized and unrealized (losses) gains | (777) | (82)
Gain (Loss) on Investments [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | (2,987) | (71)
Gain (Loss) on Investments [Member] | Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | 0 |
Gain (Loss) on Investments [Member] | Commercial Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | (7) |
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 in the period included in net realized and unrealized (losses) gains | 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 in the period included in net realized and unrealized (losses) gains | 14 | 13
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 in the period included in net realized and unrealized (losses) gains | 68 | 6
Net Investment Income Earned [Member] | Investments [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | 129 | $ 19
Net Investment Income Earned [Member] | Residential Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | 0 |
Net Investment Income Earned [Member] | Commercial Mortgage Backed Securities [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total net (losses) gains in the period included in net realized and unrealized (losses) gains | $ 47 |

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