Fair Value Measurement (Level 3 Assets) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	$ 19,234	$ 11,675	$ 11,958	$ 11,157
Included in earnings, as a part of:
Included in other comprehensive income	93	330	(66)	125
Purchases	24,006	1,406	36,238	4,828
Sales	(6,075)	(1,239)	(6,396)	(2,946)
Transfers in	0	0	3,010	1,550
Transfers out	(9,128)	(1,729)	(16,602)	(4,049)
Ending balance	27,996	10,663	27,996	10,663
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	(135)	230	(135)	8
Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	(10)	(1)	(10)
Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	(134)	230	(145)	8
Corporate Debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	7,769	3,440	3,265	5,079
Included in earnings, as a part of:
Included in other comprehensive income	13	127	33	44
Purchases	9,215	0	14,090	0
Sales	(160)	(450)	(177)	(2,157)
Transfers in	0	0	858	945
Transfers out	(1,772)	0	(3,005)	(794)
Ending balance	15,065	3,117	15,065	3,117
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Corporate Debt \| Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	1	0
Corporate Debt \| Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	0	0
Asset-backed Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	9,313	6,897	8,693	2,992
Included in earnings, as a part of:
Included in other comprehensive income	82	203	(97)	81
Purchases	8,003	1,406	15,360	4,828
Sales	(185)	(789)	(489)	(789)
Transfers in	0	0	0	605
Transfers out	(7,356)	(1,729)	(13,597)	(1,729)
Ending balance	9,857	5,978	9,857	5,978
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Asset-backed Securities \| Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	(10)	(2)	(10)
Asset-backed Securities \| Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	(11)	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	0		0
Included in earnings, as a part of:
Included in other comprehensive income	(2)		(2)
Purchases	6,583		6,583
Sales	(5,730)		(5,730)
Transfers in	0		0
Transfers out	0		0
Ending balance	852		852
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0		0
Equity securities \| Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0		0
Equity securities \| Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	1		1
Other investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	2,152	1,338	0	3,086
Included in earnings, as a part of:
Included in other comprehensive income	0	0	0	0
Purchases	205	0	205	0
Sales	0	0	0	0
Transfers in	0	0	2,152	0
Transfers out	0	0	0	(1,526)
Ending balance	2,222	1,568	2,222	1,568
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	(135)	230	(135)	8
Other investments \| Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	0	0
Other investments \| Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	$ (135)	$ 230	$ (135)	$ 8

Included in Earnings, as a part of.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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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-Name Accounting Standards Codification
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- Definition

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

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- Definition

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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- Definition

Amount of sale 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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- Definition

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

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-Name Accounting Standards Codification
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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value 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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