Comprehensive Income (Loss) - Additional Information (Detail) (USD $)	Sep. 30, 2013
Comprehensive Income Before Tax [Abstract]
Accumulated unrealized gain or loss on available-for-sale securities	$ 0

Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant