Senior Notes - Additional Information (Details) - Senior Notes [Member]	Sep. 30, 2015
Debt Instrument [Line Items]
Balance sheet leverage ratio	1.50
Maximum [Member]
Debt Instrument [Line Items]
Maximum balance sheet leverage ratio	0.63

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