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Loans Receivable (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Age of Consumer Loans contractual payments due with no forecasted future net cash flows | 120 months |
Impact of Forecast Change on Credit Losses | $ 41.6 |
Impact of Forecast Change on Finance Charges | 7.3 |
Impact of Forecast Change on Net Income | $ 30.8 |
Decrease in Forecated Net Cash Flows |  | $ 1.8

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- Definition Decrease in Forecated Net Cash Flows + References No definition available. + Details
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- Definition Impact of Forecast Change on Finance Charges + References No definition available. + Details
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- Definition Period After Consumer Loans With No Forecasted Future Net Cash Flows + 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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