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Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands |  | 9 Months Ended
--- | --- | ---
Nov. 01, 2017 | Sep. 30, 2017 | Sep. 30, 2016
Subsequent Event [Line Items] |  |  |
Repayments of Notes Payable |  | $ 394,077 | $ 1,500,000
Subsequent Event [Member] | 7.125% Notes [Member] | Unsecured Debt [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Repayments of Notes Payable | $ 103,900 |  |
Debt Instrument, Interest Rate, Stated Percentage | 7.125% |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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Balance Type: | na
Period Type: | instant

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- Definition The cash outflow for a borrowing supported by a written promise to pay an obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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- Details
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- Details
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- Details
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