Nominal or face amount used to calculate payments on the derivative asset.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Aggregate net fair value of all derivative instruments designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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Nominal or face amount used to calculate payments on the derivative liability.

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Derivative Financial Instruments - Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative instruments at fair value, less than	$ 0.1		$ 0.1
Derivative Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset	365.0
Fair Value - Asset	17.2
Recorded Gains/(Losses)	(8.7)
Derivative Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset	2,557.0
Fair Value - Asset	68.9
Recorded Gains/(Losses)	9.1
Derivative Assets \| Forward sales of MBS
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset	410.0
Fair Value - Asset	1.3
Recorded Gains/(Losses)	(0.5)
Derivative Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset	216.0
Fair Value - Asset	2.0
Recorded Gains/(Losses)	0.3
Derivative Assets \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset	7.0
Fair Value - Asset	0.0
Recorded Gains/(Losses)	0.0
Derivative Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability	0.0
Fair Value - Liability	0.0
Recorded Gains/(Losses)	0.0
Derivative Liabilities \| Forward sales of MBS
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability	3,804.0
Fair Value - Liability	21.3
Recorded Gains/(Losses)	(2.6)
Derivative Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability	52.0
Fair Value - Liability	0.2
Recorded Gains/(Losses)	(0.2)
Derivative Liabilities \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability	13.0
Fair Value - Liability	0.0
Recorded Gains/(Losses)	$ 0.0
Predecessor
Derivatives, Fair Value [Line Items]
Derivative instruments at fair value, less than		$ 0.1
Predecessor \| Derivative Assets \| Loan sale commitments
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		427.0
Fair Value - Asset		8.9
Recorded Gains/(Losses)		8.8
Predecessor \| Derivative Assets \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		1,968.0
Fair Value - Asset		57.4
Recorded Gains/(Losses)		(1.9)
Predecessor \| Derivative Assets \| Forward sales of MBS
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		1,130.0
Fair Value - Asset		5.7
Recorded Gains/(Losses)		3.3
Predecessor \| Derivative Assets \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		223.0
Fair Value - Asset		1.0
Recorded Gains/(Losses)		0.1
Predecessor \| Derivative Assets \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		331.0
Fair Value - Asset		1.3
Recorded Gains/(Losses)		(0.6)
Predecessor \| Derivative Assets \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Asset		30.0
Fair Value - Asset		0.0
Recorded Gains/(Losses)		0.0
Predecessor \| Derivative Liabilities \| IRLCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability		8.0
Fair Value - Liability		0.0
Recorded Gains/(Losses)		0.0
Predecessor \| Derivative Liabilities \| Forward sales of MBS
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability		2,384.0
Fair Value - Liability		7.3
Recorded Gains/(Losses)		4.5
Predecessor \| Derivative Liabilities \| LPCs
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability		116.0
Fair Value - Liability		0.5
Recorded Gains/(Losses)		(0.1)
Predecessor \| Derivative Liabilities \| Treasury futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability		223.0
Fair Value - Liability		1.2
Recorded Gains/(Losses)		(0.2)
Predecessor \| Derivative Liabilities \| Eurodollar futures
Derivatives, Fair Value [Line Items]
Outstanding Notional - Liability		6.0
Fair Value - Liability		0.0
Recorded Gains/(Losses)		$ 0.0