Fair Value (Activity Under Level 3, Fair Value Measurements Using Significant Unobservable Inputs By Asset Type) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
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	544,971	393,830	435,959	217,138
Total gains or (losses) (realized/unrealized) Included in earnings	1,018	(2,409)	3,229	(1,473)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	(670)	(449)	1,774	(24)
Purchases, issuances and settlements	82,289	50,308	185,127	223,889
Transfers in and/or (out) of Level 3	3,176		4,695	1,750
Ending balance	630,784	441,280	630,784	441,280
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	542,878	381,215	428,215	210,186
Total gains or (losses) (realized/unrealized) Included in earnings	1,018	(1,937)	3,348	(591)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)	(1,314)	(449)	1,130	(24)
Purchases, issuances and settlements	42,289	50,290	150,659	219,548
Transfers in and/or (out) of Level 3	3,176		4,695
Ending balance	588,047	429,119	588,047	429,119
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)	644		644
Purchases, issuances and settlements	40,000		40,000
Transfers in and/or (out) of Level 3
Ending balance	40,644		40,644
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	2,093	12,615	7,744	6,952
Total gains or (losses) (realized/unrealized) Included in earnings		(472)	(119)	(882)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)
Purchases, issuances and settlements		18	(5,532)	4,341
Transfers in and/or (out) of Level 3				1,750
Ending balance	2,093	12,161	2,093	12,161
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		3,192	2,337
Total gains or (losses) (realized/unrealized) Included in earnings		(101)	369	(257)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)		(32)
Purchases, issuances and settlements		(686)	(2,706)	2,630
Transfers in and/or (out) of Level 3
Ending balance		2,373		2,373
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] \| Foreign Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance fixed maturities		3,192	2,337
Total gains or (losses) (realized/unrealized) Included in earnings		(101)	369	(257)
Total gains or (losses) (realized/unrealized) Included in other comprehensive income (loss)		(32)
Purchases, issuances and settlements		(686)	(2,706)	2,630
Transfers in and/or (out) of Level 3
Ending balance		2,373		2,373
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

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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-Topic 820
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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 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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