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Investment in Affiliates - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended
	Oct. 12, 2018	Jun. 29, 2018	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2017
Schedule of Equity Method Investments [Line Items]
Equity in earnings of joint venture			$ 1,955	$ 1,900
Payments to noncontrolling interests			28	0
Organic Valley Fresh Joint Venture
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investment					$ 2,000
Equity in earnings of joint venture			$ 2,000	$ 1,900
Ownership interest by parent (as a percent)					50.00%
Good Karma
Schedule of Equity Method Investments [Line Items]
Ownership interest by parent (as a percent)		67.00%	69.00%
Additional investment		$ 15,000
Payments to noncontrolling interests	$ 3,000