Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions | Mar. 31, 2018 | Dec. 31, 2017 |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | $ 1,918 | $ 1,853 |
Loans held-for-sale, fair value | 4,725 | 4,300 |
Loans held-for-investment | 12 | 12 |
Mortgage servicing rights | 239 | 291 |
Total assets at fair value | 4,737 | 4,312 |
Agency - Commercial | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 1,092 | 987 |
Agency - Residential | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 750 | 794 |
Municipal obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 34 | 34 |
Corporate debt obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 42 | 38 |
Total Fair Value | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 1,918 | 1,853 |
Loans held-for-sale, fair value | 4,744 | 4,322 |
Loans held-for-investment | 8,003 | 7,667 |
Mortgage servicing rights | 239 | 291 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | (21) | (25) |
Level 1 | Total Fair Value | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Loans held-for-sale, fair value | 0 | 0 |
Loans held-for-investment | 0 | 0 |
Mortgage servicing rights | 0 | 0 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | 0 | 0 |
Level 2 | Total Fair Value | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 1,918 | 1,853 |
Loans held-for-sale, fair value | 4,744 | 4,322 |
Loans held-for-investment | 8 | 8 |
Mortgage servicing rights | 0 | 0 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | 0 | 0 |
Level 3 | Total Fair Value | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Loans held-for-sale, fair value | 0 | 0 |
Loans held-for-investment | 7,995 | 7,659 |
Mortgage servicing rights | 239 | 291 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | (21) | (25) |
Recurring | Total Fair Value | | |
Assets, Fair Value Disclosure [Abstract] | | |
Mortgage servicing rights | 239 | 291 |
Total assets at fair value | 6,939 | 6,495 |
Liabilities, Fair Value Disclosure [Abstract] | | |
DOJ litigation settlement | (60) | (60) |
Total liabilities at fair value | (110) | (96) |
Recurring | Total Fair Value | Rate lock commitments | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 30 | 24 |
Recurring | Total Fair Value | Futures | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 2 | |
Recurring | Total Fair Value | Interest rate swap on FHLB advances | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | | (1) |
Recurring | Total Fair Value | Mortgage-backed securities forwards | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 5 | 4 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | (21) | (6) |
Recurring | Total Fair Value | Interest rate swaps and swaptions | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 8 | 11 |
Recurring | Total Fair Value | Interest rate swaps | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | (8) | (4) |
Recurring | Total Fair Value | Contingent consideration | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | (21) | (25) |
Recurring | Total Fair Value | Residential first mortgage loans | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-sale, fair value | 4,725 | 4,300 |
Loans held-for-investment | 8 | 8 |
Recurring | Total Fair Value | Home equity | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-investment | 4 | 4 |
Recurring | Total Fair Value | Agency - Commercial | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 1,092 | 987 |
Recurring | Total Fair Value | Agency - Residential | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 750 | 794 |
Recurring | Total Fair Value | Municipal obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 34 | 34 |
Recurring | Total Fair Value | Corporate debt obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 42 | 38 |
Recurring | Level 1 | | |
Assets, Fair Value Disclosure [Abstract] | | |
Mortgage servicing rights | 0 | 0 |
Total assets at fair value | 0 | 0 |
Liabilities, Fair Value Disclosure [Abstract] | | |
DOJ litigation settlement | 0 | 0 |
Total liabilities at fair value | 0 | 0 |
Recurring | Level 1 | Rate lock commitments | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Recurring | Level 1 | Futures | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | |
Recurring | Level 1 | Interest rate swap on FHLB advances | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | | 0 |
Recurring | Level 1 | Mortgage-backed securities forwards | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | 0 | 0 |
Recurring | Level 1 | Interest rate swaps and swaptions | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Recurring | Level 1 | Interest rate swaps | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | 0 | 0 |
Recurring | Level 1 | Contingent consideration | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | 0 | 0 |
Recurring | Level 1 | Residential first mortgage loans | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-sale, fair value | 0 | 0 |
Loans held-for-investment | 0 | 0 |
Recurring | Level 1 | Home equity | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-investment | 0 | 0 |
Recurring | Level 1 | Agency - Commercial | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 1 | Agency - Residential | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 1 | Municipal obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 1 | Corporate debt obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 2 | | |
Assets, Fair Value Disclosure [Abstract] | | |
Mortgage servicing rights | 0 | 0 |
Total assets at fair value | 6,666 | 6,176 |
Liabilities, Fair Value Disclosure [Abstract] | | |
DOJ litigation settlement | 0 | 0 |
Total liabilities at fair value | (29) | (11) |
Recurring | Level 2 | Rate lock commitments | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Recurring | Level 2 | Futures | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 2 | |
Recurring | Level 2 | Interest rate swap on FHLB advances | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | | (1) |
Recurring | Level 2 | Mortgage-backed securities forwards | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 5 | 4 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | (21) | (6) |
Recurring | Level 2 | Interest rate swaps and swaptions | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 8 | 11 |
Recurring | Level 2 | Interest rate swaps | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | (8) | (4) |
Recurring | Level 2 | Contingent consideration | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | 0 | 0 |
Recurring | Level 2 | Residential first mortgage loans | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-sale, fair value | 4,725 | 4,300 |
Loans held-for-investment | 8 | 8 |
Recurring | Level 2 | Home equity | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-investment | 0 | 0 |
Recurring | Level 2 | Agency - Commercial | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 1,092 | 987 |
Recurring | Level 2 | Agency - Residential | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 750 | 794 |
Recurring | Level 2 | Municipal obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 34 | 34 |
Recurring | Level 2 | Corporate debt obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 42 | 38 |
Recurring | Level 3 | | |
Assets, Fair Value Disclosure [Abstract] | | |
Mortgage servicing rights | 239 | 291 |
Total assets at fair value | 273 | 319 |
Liabilities, Fair Value Disclosure [Abstract] | | |
DOJ litigation settlement | (60) | (60) |
Total liabilities at fair value | (81) | (85) |
Recurring | Level 3 | Rate lock commitments | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 30 | 24 |
Recurring | Level 3 | Futures | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | |
Recurring | Level 3 | Interest rate swap on FHLB advances | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | | 0 |
Recurring | Level 3 | Mortgage-backed securities forwards | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | 0 | 0 |
Recurring | Level 3 | Interest rate swaps and swaptions | | |
Assets, Fair Value Disclosure [Abstract] | | |
Total assets at fair value | 0 | 0 |
Recurring | Level 3 | Interest rate swaps | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Derivative liabilities | 0 | 0 |
Recurring | Level 3 | Contingent consideration | | |
Liabilities, Fair Value Disclosure [Abstract] | | |
Contingent consideration | (21) | (25) |
Recurring | Level 3 | Residential first mortgage loans | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-sale, fair value | 0 | 0 |
Loans held-for-investment | 0 | 0 |
Recurring | Level 3 | Home equity | | |
Assets, Fair Value Disclosure [Abstract] | | |
Loans held-for-investment | 4 | 4 |
Recurring | Level 3 | Agency - Commercial | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 3 | Agency - Residential | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 3 | Municipal obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | 0 | 0 |
Recurring | Level 3 | Corporate debt obligations | | |
Assets, Fair Value Disclosure [Abstract] | | |
Investment securities available-for-sale | $ 0 | $ 0 |