Statutory Requirements (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) member	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Statutory Accounting Practices [Line Items]
Liquidity ratio, minimum percentage required	75.00%
Bermuda
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	$ 1,211,102	$ 1,298,596
Required statutory capital and surplus	610,173	555,714
Statutory net income	$ 139,646	214,227	$ (272,339)
Statutory maximum percentage available for dividend payments	25.00%
Dividend payments with regulatory approval, number of members required \| member	2
Statutory amount available for dividend payments without regulatory approval	$ 316,700	314,500
United States
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	296,938	276,185
Required statutory capital and surplus	115,086	112,601
Statutory net income	$ 36,659	9,016	$ (29,491)
Statutory maximum percentage available for dividend payments	25.00%
Dividend payments with regulatory approval, number of members required \| member	2
Statutory amount available for dividend payments without regulatory approval	$ 47,400	$ 21,600
Net Worth Maintenance Agreement, Minimum Level of Capital	$ 250,000

Statutory Accounting Practices, Dividend Payments with Regulatory Approval, Number of Members Required

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- Definition

Statutory Accounting Practices, Liquidity Ratio, Minimum Percentage Required

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- Definition

Statutory Accounting Practices, Statutory Maximum Percentage Available for Dividend Payments

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- Definition

Minimum amount of net capital required to be maintained by broker-dealer parent, calculated under Aggregate Indebtedness Standard.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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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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Amount of dividends that can be declared or paid without approval of regulatory agency.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

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Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

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