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.

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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 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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Amount of purchases, (sales), issuances and (settlements) 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 (out of) level 3 of the fair value hierarchy.

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Fair Value (Activity Under Level 3, Fair Value Measurements Using Significant Unobservable Inputs By Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers in and/or (out) of Level 3			$ 4,695	$ 2,942
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Market Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities			435,959	217,138
Total gains or (losses) (realized/unrealized) Included in earnings			4,925	(752)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)			3,502	1,091
Purchases, issuances and settlements			323,898	215,540
Transfers in and/or (out) of Level 3			4,695	2,942
Ending balance			772,979	435,959
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Market Value [Member] \| Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities			428,215	210,186
Total gains or (losses) (realized/unrealized) Included in earnings			4,937	(92)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)			(20)	1,091
Purchases, issuances and settlements			179,761	215,838
Transfers in and/or (out) of Level 3			4,695	1,192
Ending balance			617,588	428,215
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Market Value [Member] \| Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities
Total gains or (losses) (realized/unrealized) Included in earnings
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)			3,632
Purchases, issuances and settlements			150,009
Transfers in and/or (out) of Level 3
Ending balance			153,641
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Market Value [Member] \| Foreign Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities			7,744	6,952
Total gains or (losses) (realized/unrealized) Included in earnings			(12)	(660)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)			(110)
Purchases, issuances and settlements			(5,872)	(298)
Transfers in and/or (out) of Level 3				1,750
Ending balance			1,750	7,744
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date
Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities			2,337
Total gains or (losses) (realized/unrealized) Included in earnings			2,163	(293)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements			1,326	2,630
Transfers in and/or (out) of Level 3
Ending balance			5,826	2,337
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date			1,795
Fair Value [Member] \| Foreign Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities			2,337
Total gains or (losses) (realized/unrealized) Included in earnings			2,163	(293)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements			1,326	2,630
Transfers in and/or (out) of Level 3
Ending balance			5,826	2,337
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date			$ 1,795