Common Unit Repurchase and Retirement - Additional Information (Detail) - USD ($) shares in Thousands		1 Months Ended			3 Months Ended	67 Months Ended
	Jul. 30, 2015	Mar. 31, 2018	Feb. 28, 2018		Mar. 31, 2018	Jan. 31, 2018	Dec. 31, 2017	Sep. 30, 2017
Capital Unit [Line Items]
Company's common units authorized for repurchase			5,500			2,200
Third Amendment
Capital Unit [Line Items]
Availability required to repurchase common units	$ 45,000,000
Percentage of the maximum facility size on a historical proforma and forward-looking basis	15.00%
Non Seasonal maximum borrowing capacity under revolving credit facility	$ 300,000,000
Minimum fixed charge coverage ratio for distributions to unit holders or to repurchase common units	115.00%
Plan III Common Units Repurchase Program
Capital Unit [Line Items]
Company's common units repurchased and retired		1,023	258		1,281	2,700
Company's common units authorized for repurchase			5,500			2,200
Total Common Units remain available for repurchase		4,219	5,242	[1]	4,219	2,207	2,207	2,207
Common Stock Available for Repurchase Under Open Market Transactions
Capital Unit [Line Items]
Company's common units authorized for repurchase			3,000
Common Stock Available for Repurchase Under Privately Negotiated Transactions
Capital Unit [Line Items]
Company's common units authorized for repurchase			2,500

[1] In February 2018, the Board authorized an increase in the number of Common Units available for repurchase from 2.2 million to 5.5 million.