Long Term Debt and Capital Leases (Net of Issuance Costs and Debt Discounts Excluding Line-of-credit Arrangements) (Parenthetical) (Detail)	4 Months Ended	12 Months Ended
Apr. 22, 2017	Dec. 31, 2016
2026 Notes
Debt Instrument [Line Items]
Senior notes due year	2026	2026
2022 Notes
Debt Instrument [Line Items]
Senior notes due year	2022	2022

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.

No definition available.

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