Long-Term Debt - Covenants - Additional Information (Details) - NMH Investment	3 Months Ended	9 Months Ended
Mar. 31, 2017	Jun. 30, 2017
Debt Instrument [Line Items]
Percentage of revolving commitments		30.00%
Consolidated first lien leverage ratio, maximum	5.00	5.50

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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