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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	3 Months Ended
	Mar. 31, 2021	Mar. 31, 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	(99)	0
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, March 31	7,896	2,890
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	(99)	0
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	(2,388)	1
Purchases	21,100	3,002
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	4,192
Transfers out of Level 3	0	0
Fair value, March 31	89,322	24,185
Period change unrealized (losses) gains in earnings for assets held at period end	(91)	(61)
Period change unrealized gains (losses) in OCI for assets held at period end	(2,388)	1
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	(1,116)	(1,756)
Purchases	10,672	4,831
Sales	0	0
Issuances	0	0
Settlements	(412)	0
Transfers into Level 3	0	20,107
Transfers out of Level 3	(490)	(3,630)
Fair value, March 31	64,889	36,372
Period change unrealized (losses) gains in earnings for assets held at period end	(143)	(214)
Period change unrealized gains (losses) in OCI for assets held at period end	(1,116)	(1,756)
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	(3,603)	(1,755)
Purchases	31,772	7,833
Sales	0	0
Issuances	0	0
Settlements	(412)	0
Transfers into Level 3	5,101	27,189
Transfers out of Level 3	(490)	(3,630)
Fair value, March 31	162,107	63,447
Period change unrealized (losses) gains in earnings for assets held at period end	(234)	(275)
Period change unrealized gains (losses) in OCI for assets held at period end	(3,603)	(1,755)
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	(91)	(61)
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	(143)	(214)
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	(234)	(275)
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	1	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	0
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	$ 4	$ 0

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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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