Statutory Information (Details) $ in Millions	6 Months Ended
	Jun. 30, 2022 USD ($) jurisdiction
Statutory capital requirements [Abstract]
Number of jurisdictions with risk-to-capital requirements (in jurisdictions) | jurisdiction	16
Maximum permitted risk-to-capital ratio commonly applied	25 to 1
Mortgage Guaranty Insurance Corporation
Statutory capital requirements [Abstract]
Maximum risk-to-capital ratio	25
Risk to capital ratio at end of period	9.7 to 1
Risk-to-capital ratio	9.7
Amount of policyholders position above or below required MPP	$ 3,500
Amount of required MPP	1,900
Dividend paid to the holding company	$ 400
Percentage of statutory policyholders surplus used to determine maximum allowable dividends (as a percent)	10.00%
Adjusted statutory net income measurement period (in years)	3 years
Adjusted statutory net income dividend payment measurement period (in years)	2 years