Revenue and Components of Net Income Related to Discontinued Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net income from discontinued operations		[1]	$ 170
Basic and diluted net income per share on discontinued operations		[1]	$ 0.01
Segment, Discontinued Operations
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Revenue			590
Income from discontinued operations before income taxes			284
Provision for income taxes			(114)
Net income from discontinued operations			$ 170
Basic and diluted net income per share on discontinued operations			$ 0.01

[1] Restated and Revised, see Note 2