Debt - Schedule of Principal Repayment under the Financing Agreement (Detail) - Term Loan [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2015 USD ($)
2015 [Member] | March 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	$ 2,500
2015 [Member] | June 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	2,500
2015 [Member] | September 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	2,500
2015 [Member] | December 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	2,500
2016 [Member] | March 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	5,000
2016 [Member] | June 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	5,000
2016 [Member] | September 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	5,000
2016 [Member] | December 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	5,000
2017 [Member] | March 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	7,500
2017 [Member] | June 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	7,500
2017 [Member] | September 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	7,500
2017 [Member] | December 1 [Member]
Debt Instrument [Line Items]
Debt instrument installment amount	$ 47,500