Fair Value Measurements - Changes in Estimated Fair Value of Contingent Consideration Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2013	$ 7,735	$ 8,808
Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2013	7,735	8,808
Cash payments	1,116
Losses recorded for fair value adjustments	42
Unrealized loss on foreign currency translation	1
Balance at June 30, 2014	7,735
Commitments [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2013	7,735	8,808
Commitments [Member] | Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2013	$ 7,735	$ 8,808