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Derivative Financial Instruments (Narrative) (Details) - Swap [Member] - FFL [Member] - USD ($) $ in Millions |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Feb. 13, 2014 | Dec. 31, 2019 | Dec. 31, 2018 | Jul. 31, 2018 | Jan. 31, 2018
Derivative Financial Instruments [Line Items] |  |  |  |  |
Derivative, notional amount |  |  | $ 100 |  |
Term of swap agreement | 1 year | 1 year |  |  |
LIBOR [Member] |  |  |  |  |
Derivative Financial Instruments [Line Items] |  |  |  |  |
Basis spread on variable rate | 1.28% |  |  | 1.05% | 1.20%

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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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- Definition The percentage points added to the reference rate to compute the variable rate on the interest rate derivative. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Details
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- Details
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- Details
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