Other (Loss) Income, net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Other Income and Expenses [Abstract]
Proceeds from sales / distributions of ownership interests	$ 30	$ 1,000
Loan repayment from equity / cost method investment	$ 16	$ 400

Debt repayment from equity method or cost method investment.

No definition available.

Name:	acta_DebtRepaymentFromEquityMethodOrCostMethodInvestment
Namespace Prefix:	acta_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration