Loans (Narrative) (Details)	12 Months Ended
	Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	$ 172,700,000	$ 221,800,000
Period past due when loans go into non accrual status	90 days
Recorded investment in loans with modifications	$ 103,500,000	$ 82,300,000
Percentage of TDRs on non-accrual	63.00%	41.00%
Commitments to lend to borrowers whose loans terms have been modified in TDRs	$ 13,400,000	$ 5,400,000
Recorded investment related to modifications qualifying as TDRs	$ 92,500,000	80,500,000
Number of payments for default of TDR | loan	1
Recorded investment of TDRs that experience a payment default within one year of the modification	$ 47,000,000	$ 11,300,000
Payments deferral rate for TDRs	31.00%	12.00%
Covenant relief rate for TDRs	69.00%	88.00%
PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchase discount on repurchased loans		$ 9,100,000
Reverse Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans in portfolio | loan	1,500
Unpaid principal balance of portfolio	$ 944,000,000
HAMP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in trial modification period	300,000	36,400,000
2MP
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in trial modification period		100,000
Proprietary Programs
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in trial modification period	12,200,000	3,000,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	$ 500,000
Trial payment period for consumer borrowers experiencing financing difficulty	3 months
Principal as a percent of maximum claim amount for which company is required to repurchase loans	98.00%
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trial payment period for consumer borrowers experiencing financing difficulty	4 months
Small Commercial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period past due when loans go into non accrual status	90 days
Real Estate Mortgage Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period past due when loans go into non accrual status	120 days
Accruing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in loans with modifications	$ 12,300,000	38,100,000
Non-Accruing Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in loans with modifications	$ 200,000	$ 1,400,000
Reverse Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans in portfolio | loan		1,700
Unpaid principal balance of portfolio		$ 1,027,900,000
Average borrower age in portfolio		83 years
Reverse Mortgages, HFI
Accounts, Notes, Loans and Financing Receivable [Line Items]
Service loans accounted for under the effective yield method		$ 30,400,000
Commercial Banking
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of investment in TDRs	83.00%	85.00%
Defaults on TDRs	93.00%
Consumer Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of investment in TDRs	17.00%	15.00%
Defaults on TDRs		7.00%
Consumer Banking | Reverse Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans		$ 859,000,000
Consumer Banking | Reverse Mortgages Uninsured
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans		769,600,000
HECM Reverse Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans	$ 136,300,000	122,200,000
Payments to repurchase loans	118,000,000
HECM Reverse Mortgages | Reverse Mortgages, AHFS
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans	177,600,000	32,800,000
HECM Reverse Mortgages | Reverse Mortgages, HFI
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchase discount on repurchased loans		68,100,000
Consumer Banking | Commercial Banking
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans with terms that permit negative amortization	484,000,000	$ 761,000,000
Financial Freedom | Discontinued Operations, Held-for-sale | Consumer Banking | Reverse Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans	861,000,000
Financial Freedom | Discontinued Operations, Held-for-sale | Consumer Banking | Reverse Mortgages Uninsured
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance of loans	$ 724,700,000