Other Assets - Schedule of Other Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Loans subject to repurchase right from Ginnie Mae	$ 560.0		$ 266.0
Derivative financial instruments	153.0		49.0
Trade receivables and accrued revenues	126.0		145.0
Right-of-use assets	121.0	$ 114.0	0.0
Goodwill	120.0		23.0
Intangible assets	74.0		117.0
Other	236.0		195.0
Total other assets	$ 1,390.0		$ 795.0

Assets Sold Under Agreements to Repurchase, Loan Receivable

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Servicing Fees Receivable

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of assets classified as other.

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Amount of other miscellaneous assets.

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