Investments in Unconsolidated Affiliates - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Schedule of Equity Method Investments [Line Items]
Equity in earnings of joint venture	$ 1,917	$ 0	$ 5,516	$ 0
Organic Valley Fresh Joint Venture
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)		50.00%		50.00%
Payments to acquire equity method investment		$ 2,000
Distributions from joint venture			2,800
Equity in earnings of joint venture	$ (1,900)		$ (5,500)

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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