Advances and Other Receivables, Net - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2019	Feb. 01, 2019	Dec. 31, 2018	Aug. 01, 2018	Jul. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable discount	$ 21		$ 48		$ 56
Pacific Union Financial, LLC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable discount		$ 19
WMIH Corp And Wand Merger Corporation
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable discount	152			$ 302
Purchase discount utilized	$ 169