Reconciliation for Liabilities Measured at Fair Value on Recurring Basis using Significant Unobservable Inputs (Level Three) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Common stock warrant liability
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 7,500	$ 2,000	$ 2,350	$ 1,403
Income (Expense) Realized in Earnings	(3,300)	(850)	(8,450)	(1,447)
Transfers In/Out of Level 3
Purchases
Issuances
Settlements
Ending Balance	10,800	2,850	10,800	2,850
Contingent consideration
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance		3,746		3,597
Income (Expense) Realized in Earnings		(76)		(225)
Transfers In/Out of Level 3
Purchases
Issuances
Settlements
Ending Balance		$ 3,822		$ 3,822