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Basis of Presentation - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Percentage of comparable consolidated amounts	95.00%	95.00%

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- Definition

Percentage of comparable consolidated amount.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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