Other Assets - Schedule of Others Assets (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Other Assets [Line Items]
Loans subject to repurchase right from Ginnie Mae	$ 231
Accrued revenues	144
Intangible assets	117
Derivative financial instruments at fair value	72
Prepaid expenses	31
REO, net	19
Deposits	15
Goodwill	3
Receivables from affiliates, net	0
Other	167
Total other assets	$ 799
Predecessor
Other Assets [Line Items]
Loans subject to repurchase right from Ginnie Mae		$ 218
Accrued revenues		148
Intangible assets		19
Derivative financial instruments at fair value		65
Prepaid expenses		27
REO, net		23
Deposits		19
Goodwill		72
Receivables from affiliates, net		6
Other		82
Total other assets		$ 679