Consolidated Statements of Operations - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Interest Income              
Loans $ 82 $ 74 $ 166 $ 139 $ 295 $ 246 $ 313
Investment securities 17 15 34 29 59 39 12
Interest-earning deposits and other 0 1 0 1 1 1 5
Total interest income 99 90 200 169 355 286 330
Interest Expense              
Deposits 11 11 22 20 42 30 42
Federal Home Loan Bank advances 8 4 15 7 18 2 95
Short-term debt 1 0 3 0      
Other 2 2 4 4 8 7 7
Total interest expense 22 17 44 31 68 39 144
Net interest income 77 73 156 138 287 247 186
(Benefit) provision for loan losses (3) (13) (16) (17) (19) 132 70
Net interest income after provision for loan losses 80 86 172 155 306 115 116
Noninterest Income              
Net gain on loan sales 90 83 165 174 288 206 402
Loan fees and charges 19 19 34 36 67 73 104
Deposit fees and charges 6 6 12 12 25 22 21
Loan administration income 4 7 10 11 26 24 6
Net return on mortgage servicing asset         28 24 91
Net (loss) gain on sale of assets 0 (2) (2) (2) (1) 12 2
Net impairment losses         0 0 (9)
Representation and warranty benefit (provision) 4 5 6 7 19 (10) (36)
Other noninterest income         18 10 72
Total noninterest income 128 126 233 245 470 361 653
Noninterest Expense              
Compensation and benefits 66 59 134 120 237 233 279
Commissions 14 11 24 21 39 35 54
Occupancy and equipment 21 20 43 40 81 80 80
Asset resolution 1 5 4 13 15 57 52
Federal insurance premiums 3 6 6 12 23 23 35
Loss on extinguishment of debt         0 0 178
Loan processing expense 15 14 27 26 52 37 52
Legal and professional expense 6 8 15 17 36 51 78
Other noninterest expense 13 15 23 27 53 63 110
Noninterest Income, Other Operating Income (Loss) 9 (1) 18 0      
Total noninterest expense 139 138 276 276 536 579 918
Income (loss) before income taxes 69 74 129 124 240 (103) (149)
Provision (benefit) for income taxes 22 28 43 46 82 (34) (416)
Net income (loss) $ 47 $ 46 $ 86 $ 78 158 (69) 267
Preferred stock dividend/accretion         0 (1) (6)
Net income (loss) from continuing operations         $ 158 $ (70) $ 261
Earnings (loss) per share              
Basic (in usd per share) $ 0.67 $ 0.69 $ 1.23 $ 1.12 $ 2.27 $ (1.72) $ 4.40
Diluted (in usd per share) $ 0.66 $ 0.68 $ 1.21 $ 1.11 $ 2.24 $ (1.72) $ 4.37
Weighted average shares outstanding              
Basic (in shares) 56,574,796 56,436,026 56,544,256 56,410,880 56,426,977 56,246,528 56,063,282
Diluted (in shares) 57,751,230 57,165,072 57,623,081 56,971,133 57,164,523 56,246,528 56,518,181