Geographic Areas and Product Sales - Net Sales by Product (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Revenue from External Customer [Line Items]
Net sales	$ 60,057	$ 46,419	$ 58,310	$ 39,318	$ 52,092	$ 36,319	$ 46,651	$ 34,410	$ 204,104	$ 169,472	$ 141,481
Meals
Revenue from External Customer [Line Items]
Net sales									99,004	79,006	60,680
Snacks
Revenue from External Customer [Line Items]
Net sales									79,074	66,662	56,868
Dressings, Condiments and Other
Revenue from External Customer [Line Items]
Net sales									$ 26,026	$ 23,804	$ 23,933