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Financing Arrangements - Additional Information (Detail) | Jun. 30, 2018 DebtFinancing | Jun. 29, 2018 USD ($) | Dec. 31, 2017 DebtFinancing
--- | --- | --- | ---
Debt Instrument [Line Items] |  |  |
Number of debt financing | DebtFinancing | 0 |  | 0
Merger Sub [Member] | Senior Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issued aggregate principal amount |  | $ 1,700,000,000 |
Merger Sub [Member] | Senior Notes [Member] | Notes due 2023 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issued aggregate principal amount |  | $ 950,000,000 |
Stated interest rate |  | 8.125% |
Merger Sub [Member] | Senior Notes [Member] | Notes due 2026 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Issued aggregate principal amount |  | $ 750,000,000 |
Stated interest rate |  | 9.125% |

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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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- Details
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