The Company - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Oct. 05, 2016	Sep. 27, 2016	Dec. 31, 2016
Nature Of Operations [Line Items]
Purchase price to be paid by IRT			$ 43,000
IRT
Nature Of Operations [Line Items]
Purchase price to be paid by IRT		$ 43,000
IRT | Common Shares
Nature Of Operations [Line Items]
Number of shares sold to IRT	7,269,719
Proceeds form sale of shares	$ 62,156