v3.7.0.1

Condensed Consolidating Financial Information - Additional Information (Detail) | Mar. 31, 2017 USD ($)
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Supplemental Guarantor Financial Information [Line Items] |
Ownership percentage in domestic subsidiaries | 100.00%
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member] |
Supplemental Guarantor Financial Information [Line Items] |
Senior notes, amount issued | $ 500,000,000
Interest rate on Senior Notes | 5.25%

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