Basis of Presentation and Recently Issued Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands		6 Months Ended
	Jan. 01, 2018	Jun. 30, 2018
Minimum [Member]
Significant Accounting Policies [Line Items]
Retail operations period of fiscal year		364 days
Retail operations period of fiscal quarter		91 days
Maximum [Member]
Significant Accounting Policies [Line Items]
Retail operations period of fiscal year		371 days
Retail operations period of fiscal quarter		98 days
Customer Payments [Member] | Accounting Standards Update 2014-09 [Member]
Significant Accounting Policies [Line Items]
Increase (decrease) in retained earnings	$ (46)
Metallic Balloon Sales [Member] | Accounting Standards Update 2014-09 [Member]
Significant Accounting Policies [Line Items]
Increase (decrease) in retained earnings	8
Discount Sale [Member] | Accounting Standards Update 2014-09 [Member]
Significant Accounting Policies [Line Items]
Increase (decrease) in retained earnings	$ (40)