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Basis of Presentation and Significant Accounting Policies - Narrative (Details) - segment | 9 Months Ended |
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Sep. 30, 2017 | Aug. 14, 2017
Schedule of Equity Method Investments [Line Items] |  |
Number of segments | 2 |
Residential Mortgage Holding Company |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 100.00% |
NBG |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage |  | 50.10%

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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