Segment Information - Key Servicing Metrics (Details) - Agency Business - MSRs - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Segment Information
Servicing Portfolio UPB	$ 27,065,127	$ 26,959,389
Wtd. Avg. Servicing Fee Rate (basis points)	42.40%	44.90%
Wtd. Avg. Life of Servicing Portfolio (in years)	8 years 10 months 24 days	8 years 9 months 18 days
SFR - Fixed Rate
Segment Information
Servicing Portfolio UPB	$ 241,887	$ 191,698
Wtd. Avg. Servicing Fee Rate (basis points)	20.00%	20.00%
Wtd. Avg. Life of Servicing Portfolio (in years)	6 years 2 months 12 days	6 years 6 months
Fannie Mae
Segment Information
Servicing Portfolio UPB	$ 18,331,457	$ 19,127,397
Wtd. Avg. Servicing Fee Rate (basis points)	52.10%	53.50%
Wtd. Avg. Life of Servicing Portfolio (in years)	8 years 3 months 18 days	8 years
Freddie Mac
Segment Information
Servicing Portfolio UPB	$ 4,979,612	$ 4,943,905
Wtd. Avg. Servicing Fee Rate (basis points)	26.00%	27.10%
Wtd. Avg. Life of Servicing Portfolio (in years)	9 years 6 months	9 years 3 months 18 days
Private Label
Segment Information
Servicing Portfolio UPB	$ 2,075,791	$ 1,711,326
Wtd. Avg. Servicing Fee Rate (basis points)	20.00%	20.00%
Wtd. Avg. Life of Servicing Portfolio (in years)	8 years 2 months 12 days	8 years 3 months 18 days
FHA
Segment Information
Servicing Portfolio UPB	$ 1,136,684	$ 985,063
Wtd. Avg. Servicing Fee Rate (basis points)	14.90%	15.40%
Wtd. Avg. Life of Servicing Portfolio (in years)	19 years 9 months 18 days	21 years
Bridge loans
Segment Information
Servicing Portfolio UPB	$ 299,696
Wtd. Avg. Servicing Fee Rate (basis points)	12.50%
Wtd. Avg. Life of Servicing Portfolio (in years)	2 years 3 months 18 days