Indemnification Assets (Narrative) (Details)	12 Months Ended		77 Months Ended
	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Aug. 02, 2015 USD ($)
Indemnification Assets [Line Items]
Number of days before reimbursement approval by FDIC	60 days
Amount FDIC indemnifies against losses	$ 142,400,000	$ 341,400,000
SFR
Indemnification Assets [Line Items]
Excess losses reimbursed by FDIC, percent	80.00%
IndyMac Transaction
Indemnification Assets [Line Items]
Net amortization on indemnification assets	$ 47,000,000	22,000,000
Number of components to indemnification program | segment	3
Amount FDIC indemnifies against losses	$ 142,400,000	341,400,000
Advance on reverse mortgage loan	134,400,000	145,200,000
Cumulative loss submissions and reimbursements			$ 1,800,000
Reimbursement from FDIC for cumulative losses	2,900,000
Agency claims indemnification	28,900,000	108,000,000
Reverse mortgage indemnification released	77,000,000
Reverse mortgage indemnification	0	10,400,000
IndyMac Transaction | SFR
Indemnification Assets [Line Items]
First loss tranche	2,551,000,000
Final loss threshold	$ 3,826,000,000
Excess loss reimbursement at final loss threshold, percent	95.00%
Amount reinbursed by FDIC			5,700,000
IndyMac Transaction | SFR, Servicing Obligations Prior to March 2009
Indemnification Assets [Line Items]
Agency claims indemnification	$ 0
Reverse mortgage indemnification	29,000,000
IndyMac Transaction | Reverse Mortgage Indemnification Assets
Indemnification Assets [Line Items]
Cumulative loss submissions			11,200,000
Cumulative reimbursements related to reverse mortgage loans sold to agencies			$ 10,700,000
IndyMac Transaction | Reverse Mortgage Indemnification Assets | Minimum
Indemnification Assets [Line Items]
FDIC fund advances threshold	200,000,000
IndyMac Transaction | Reverse Mortgage Indemnification Assets | Maximum
Indemnification Assets [Line Items]
Amount FDIC indemnifies against losses	200,000,000
First Federal Transaction
Indemnification Assets [Line Items]
First loss tranche	$ 932,000,000
First Federal Transaction | Commercial Loans
Indemnification Assets [Line Items]
Extendable period	3 years
La Jolla Transaction
Indemnification Assets [Line Items]
FDIC true-up liability	$ 65,100,000	$ 61,900,000
La Jolla Transaction | Commercial Loans
Indemnification Assets [Line Items]
Extendable period	3 years
La Jolla Transaction | SFR
Indemnification Assets [Line Items]
Excess losses reimbursed by FDIC, percent	80.00%
Final loss threshold	$ 1,007,000,000