Acquisitions - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Business Acquisition, Contingent Consideration [Line Items]
Consideration paid in cash	$ 1,500,000	$ 900,000
CBIZ contingent consideration	10,200,000
Consideration paid in common stock	1,900,000
Goodwill	20,610,000
Fair value of contingent consideration	1,000,000	900,000
Number of common stock issued		99,000
Centric Insurance Agency (Centric), Clearview National Partners, LLC (Clearview) and Lewis Birch & Richardo, LLC (LBR) [Member]
Business Acquisition, Contingent Consideration [Line Items]
Number of businesses acquired	3
Consideration paid in cash	16,500,000
Contingent arrangements arising from acquisitions	10,900,000
Fair value of contingent consideration	10,200,000
Goodwill	$ 20,600,000