Class A Redeemable Convertible Preferred Stock - Summary of Product of Paid-in-kind Dividend Rate (Detail) - Series A Redeemable Convertible Preferred Stock [Member]	12 Months Ended
	Dec. 31, 2015
Commencing on the Original Issue Date and Ending on the 1st Anniversary of Original Issue Date [Member]
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	0.00%
Commencing on the Day After the 1st Anniversary of the Original Issue Date and Ending on the 4th Anniversary of the Original Issue Date [Member]
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	4.00%
Commencing on the Day After the 4th Anniversary of the Original Issue Date and Ending on the 5th Anniversary of the Original Issue Date
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	5.00%
Commencing on the Day After the 5th Anniversary of the Original Issue Date and Ending on the 6th Anniversary of the Original Issue Date
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	6.00%
Commencing on the Day After the 6th anniversary of the Original Issue Date and Ending on the 7th Anniversary of the Original Issue Date
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	7.00%
Commencing on the Day After the 7th Anniversary of the Original Issue Date and Ending on the 8th Anniversary of the Original Issue Date
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	8.00%
Commencing on the Day After the 8th Anniversary of the Original Issue Date and Ending on the 9th Anniversary of the Original Issue Date
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	9.00%
Commencing on the Day After the 9th Anniversary of the Original Issue Date and Ending on the date of Automatic Conversion
Temporary Equity [Line Items]
PIK Dividend Rate per Annum in Effect	10.00%