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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, 2021	Jun. 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	(13)	(111)
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, June 30	7,982	2,779
Period change unrealized (losses) gains in earnings for assets held at period end	0	0
Period change unrealized gains (losses) in OCI for assets held at period end	(13)	(111)
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	1,899	(1,770)
Purchases	25,403	3,002
Sales	0	0
Issuances	0	0
Settlements	(167)	(138)
Transfers into Level 3	0	4,592
Transfers out of Level 3	(7,454)	0
Fair value, June 30	90,405	22,353
Period change unrealized (losses) gains in earnings for assets held at period end	11	(384)
Period change unrealized gains (losses) in OCI for assets held at period end	1,899	(1,770)
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	396	(367)
Purchases	17,639	9,690
Sales	0	0
Issuances	0	0
Settlements	(1,429)	(1,032)
Transfers into Level 3	3,226	20,107
Transfers out of Level 3	(5,394)	(9,924)
Fair value, June 30	70,737	35,160
Period change unrealized (losses) gains in earnings for assets held at period end	(82)	(349)
Period change unrealized gains (losses) in OCI for assets held at period end	396	(367)
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	2,282	(2,248)
Purchases	43,042	12,692
Sales	0	0
Issuances	0	0
Settlements	(1,596)	(1,170)
Transfers into Level 3	8,327	27,589
Transfers out of Level 3	(12,848)	(9,924)
Fair value, June 30	169,124	60,292
Period change unrealized (losses) gains in earnings for assets held at period end	(71)	(733)
Period change unrealized gains (losses) in OCI for assets held at period end	2,282	(2,248)
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	11	(384)
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	(82)	(349)
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	(71)	(733)
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	13	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	6	1
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	$ 19	$ 1

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Change in unrealized gains (losses) for the period included in comprehensive income for assets held at the end of the period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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