Business Combinations - Summary of Unaudited ProForma Financial Information (Detail) - HealthLine Systems LLC [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Business Acquisition [Line Items]
Total revenues			$ 2,606
Operating loss			(1,170)
Total revenues	$ 55,231	$ 54,604	110,265	$ 106,213
Net income	$ 1,656	$ 2,909	$ 3,730	$ 6,840
Basic earnings per share	$ 0.05	$ 0.10	$ 0.12	$ 0.24
Diluted earnings per share	$ 0.05	$ 0.10	$ 0.12	$ 0.24

Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

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