Derivatives and Fair Value Measurements - Narrative (Details) - Foreign currency forward contract AUD in Millions	Jun. 30, 2017 AUD AUD / $
Derivatives, Fair Value [Line Items]
Derivative, notional amount \| AUD	AUD 940.0
Derivative, exchange rate cap \| AUD / $	0.77

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant