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Derivative Financial Instruments (Narrative) (Details) - USD ($) $ in Millions |  | 6 Months Ended
--- | --- | ---
Aug. 09, 2013 | Jun. 30, 2015
Derivative Financial Instruments [Line Items] |  |
Document Period End Date |  | Jun. 30, 2015
2014 Swap [Member] |  |
Derivative Financial Instruments [Line Items] |  |
Notional amount |  | $ 111
Swap agreement collateral |  | 30
Term of swap agreement | 1 year |
2013 Swap [Member] |  |
Derivative Financial Instruments [Line Items] |  |
Notional amount |  | 152
Swap agreement collateral |  | $ 40
Term of swap agreement | 3 years |
LIBOR [Member] | 2014 Swap [Member] |  |
Derivative Financial Instruments [Line Items] |  |
Basis spread on variable rate |  | 1.35%
LIBOR [Member] | 2013 Swap [Member] |  |
Derivative Financial Instruments [Line Items] |  |
Basis spread on variable rate |  | 1.20%

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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + 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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- 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 Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + 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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