Debt (Secured Bank Term Loans) - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2019	Mar. 31, 2019
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding letters of credit	$ 8.4	$ 8.5

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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Balance Type:	na
Period Type:	duration