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Basis of Presentation and Significant Accounting Policies Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Jun. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Gain on sale of merchant card services portfolio | $ 14,000,000 |  | $ 0 | $ 14,000,000 | $ 0
Merchant Card Services Agreement [Member] |  |  |  |  |
Net carrying amount of merchant card services portfolio upon sale |  | $ 0 |  |  |
Net revenue share - merchant card services | 438,000 |  |  |  |
Gain on sale of merchant card services portfolio | $ 14,000,000 |  |  |  |

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- Details
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