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Reinsurance - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended
	Apr. 01, 2019	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Ceded Credit Risk [Line Items]
Restricted cash			$ 2,505		$ 2,662
Reinsurance recoverable on unpaid claims		$ 3,678	$ 6,193	$ 3,678	$ 4,939	$ 3,001
ILN Transactions
Ceded Credit Risk [Line Items]
Reinsurance coverage amount amortized (as a percent)			10.00%
Third-Party Reinsurers | ILN Transactions | Maximum
Ceded Credit Risk [Line Items]
Reinsurance coverage, term of underlying mortgage amortization (in years)			10 years
Third-Party Reinsurers | 2017 ILN Transaction
Ceded Credit Risk [Line Items]
Risk premiums paid			$ 3,900	$ 3,000
Third-Party Reinsurers | 2017 ILN Transaction | Maximum
Ceded Credit Risk [Line Items]
Anticipated payment related to annual operating expenses			300
Third-Party Reinsurers | 2018 ILN Transaction | Maximum
Ceded Credit Risk [Line Items]
Anticipated payment related to annual operating expenses			$ 250
Third-Party Reinsurers | QSR Transactions
Ceded Credit Risk [Line Items]
Ceding commissions under 2016 QSR Transaction			20.00%
Reinsurance recoverable on unpaid claims			$ 6,200
Third-Party Reinsurers | Risk Written Policies in 2018
Ceded Credit Risk [Line Items]
Percent of premiums earned under 2018 QSR Transaction			25.00%
Third-Party Reinsurers | Risk Written Policies in 2019
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction			20.00%
Third-Party Reinsurers | 2018 QSR Transaction
Ceded Credit Risk [Line Items]
Threshold for loss ratio on loans to qualify for profit commission			61.00%
Reinsurance recoverable on unpaid claims			$ 3,100
Third-Party Reinsurers | 2016 QSR Transaction
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction	20.50%	25.00%
Previously ceded primary RIF recaptured	$ 500,000
Threshold for loss ratio on loans to qualify for profit commission			60.00%
Reinsurance recoverable on unpaid claims			$ 3,100
Third-Party Reinsurers | Fannie Mae
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction			100.00%
Third-Party Reinsurers | Eligible Policies, Pool One
Ceded Credit Risk [Line Items]
Percent of premiums ceded under QSR Transaction			25.00%

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Amount, after valuation allowance, recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts.

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