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Contingencies and Other Disclosures (Details) - USD ($) shares in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Dec. 31, 2017
Loss Contingencies [Line Items] |  |  |
Estimated litigation liability | $ 32,900,000 |  |
Accrued losses on loan repurchase exposure | 32,300,000 |  | $ 34,200,000
Visa Class B Shares |  |  |
Loss Contingencies [Line Items] |  |  |
Number of Visa Class B shares (in shares) |  | 2.4 |
Mortgage Securitization Litigation |  |  |
Loss Contingencies [Line Items] |  |  |
Investment in proprietary securitizations subject to lawsuits | 83,400,000 |  |
Investment in proprietary securitizations subject to indemnifications | 231,200,000 |  |
Minimum |  |  |
Loss Contingencies [Line Items] |  |  |
Estimated reasonably possible losses in excess of currently established liabilities |  | $ 0 |
Maximum |  |  |
Loss Contingencies [Line Items] |  |  |
Estimated reasonably possible losses in excess of currently established liabilities | $ 20,000,000 |  |

X
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- Definition Total amount of indemnities claimed by plaintiffs to have invested in proprietary securitizations and seeking repurchase of investments. + References No definition available. + Details
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- Definition Total amount of lawsuitss claimed by plaintiffs to have invested in proprietary securitizations and seeking repurchase of investments. + References No definition available. + Details
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- Definition Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.25) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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