Goodwill and Intangible Assets - Schedule of Intangible Assets (Parenthetical) (Detail) $ in Millions	6 Months Ended
Sep. 30, 2015 USD ($)
Non-compete Agreements [Member]
Intangible Assets [Line Items]
Write off of expired and fully amortized intangible assets	$ (2.3)

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. Information by type or class of assets having a projected finite and indefinite period of benefit.

No definition available.

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Period Type:	duration