Fair Value Measurements - Reconciliation of Beginning and Ending Balances of Contingent Consideration Liability Categorized Under Level 3 of Fair Value (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total (gains) losses for period: Included in net income	$ 3,000	$ (215,000)
Contingent Consideration [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening balance	685,000
Transfers into level 3	0
Transfers out of level 3	0
Total (gains) losses for period: Included in net income	(3,000)
Total gains or losses for period Included in other comprehensive income	0
Purchases	0
Sales	0
Settlements	0
Issuances	0
Closing balance	$ 682,000