Reinsurance - Variable Interest Entity (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Home Re special purpose insurers
Effects of Reinsurance [Line Items]
Amortization period excess of loss reinsurance coverage	10 years
Term of mortgage insurance-linked notes	10 years
Remaining First Layer Retention	$ 352,625	$ 353,415
Remaining Excess of Loss Reinsurance Coverages	$ 463,275	531,978
Percent of total trust assets invested in cash or direct U.S. federal government obligations	99.50%
Home Re 2018-1
Effects of Reinsurance [Line Items]
Remaining First Layer Retention	$ 167,328	167,779
Remaining Excess of Loss Reinsurance Coverages	233,626	260,957
Total VIE Assets	245,314	269,451
Home Re 2019-1
Effects of Reinsurance [Line Items]
Remaining First Layer Retention	185,297	185,636
Remaining Excess of Loss Reinsurance Coverages	229,649	271,021
Total VIE Assets	$ 247,276	$ 283,150

Amortization Period Excess of Loss Reinsurance Coverage

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- Definition

Reinsurance Retention Policy, Debt Issued To Cover Insurance, Term

+ References

No definition available.

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- Definition

Reinsurance Retention Policy, Percent Of Total Trust Assets Invested In Cash Or Direct U.S. Federal Government Obligations

+ References

No definition available.

+ Details

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- Definition

Reinsurance Retention Policy, Remaining Excess of Loss Reinsurance Coverages

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Stated amount that is the upper retention limit per entity policy.

+ References

No definition available.

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

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