v3.8.0.1

Available for Sale Investments, at Fair Value - Continuous Unrealized Losses (Details) - Fixed Maturities $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Fair value, less than 12 months	$ 53,147
Unrealized losses, less than 12 months	(74)
Fair value, 12 months or longer	0
Unrealized losses, 12 months or longer	0
Fair Value	53,147
Unrealized Losses	(74)
Treasury Bills
Schedule Of Available For Sale Securities [Line Items]
Fair value, less than 12 months	33,978
Unrealized losses, less than 12 months	(36)
Fair value, 12 months or longer	0
Unrealized losses, 12 months or longer	0
Fair Value	33,978
Unrealized Losses	(36)
US Treasury securities
Schedule Of Available For Sale Securities [Line Items]
Fair value, less than 12 months	19,169
Unrealized losses, less than 12 months	(38)
Fair value, 12 months or longer	0
Unrealized losses, 12 months or longer	0
Fair Value	19,169
Unrealized Losses	$ (38)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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Amount of unrealized loss on securities classified as available-for-sale.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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- Definition

Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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