Income Per Share - Additional Information (Detail)	12 Months Ended
Dec. 31, 2012
Schedule of Earnings Per Share, Basic and Diluted, by Common Class
Shares Excluded from Computation of Weighted average diluted Shares outstanding	5,390

Shares Excluded From Diluted Weighted Average Common Shares Outstanding Computation Due To Operating Losses

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration