Disposal and Discontinued Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense	$ 0	$ 0	$ (2,122)
Clinical Trial Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue			7,939
Income from discontinued operations before gain on sale and income taxes			434
Gain on sale of discontinued operations			3,969
Income tax expense			(2,122)
Income from discontinued operations, net of income taxes			$ 2,281