Earnings (Loss) Per Share - Reconciliation of Numerators and Denominators Used in Computations of Both Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net (income) loss attributable to non-controlling interest	$ 0	$ 0	$ 0	$ 0
Basic earnings (loss) per share computation:
Income (loss) from continuing operations	(42,016)	17,647	(42,281)	7,888
Net (income) loss attributable to non-controlling interest	0	0	0	0
Income (loss) from continuing operations attributable to Dean Foods Company	$ (42,016)	$ 17,647	$ (42,281)	$ 7,888
Average common shares	91,342,652	90,882,415	91,267,748	90,796,585
Basic earnings (loss) per share from continuing operations (USD per share)	$ (0.46)	$ 0.19	$ (0.46)	$ 0.09
Diluted earnings (loss) per share computation:
Income (loss) from continuing operations	$ (42,016)	$ 17,647	$ (42,281)	$ 7,888
Net (income) loss attributable to non-controlling interest	0	0	0	0
Income (loss) from continuing operations attributable to Dean Foods Company	$ (42,016)	$ 17,647	$ (42,281)	$ 7,888
Average common shares — basic	91,342,652	90,882,415	91,267,748	90,796,585
Average common shares — diluted	91,342,652	91,369,030	91,267,748	91,365,946
Diluted earnings (loss) per share from continuing operations (USD per share)	$ (0.46)	$ 0.19	$ (0.46)	$ 0.09
Stock options
Diluted earnings (loss) per share computation:
Stock option conversion	0	220,318	0	232,495
RSUs and PSUs
Diluted earnings (loss) per share computation:
Stock option conversion	0	266,297	0	336,866
Stock options
Diluted earnings (loss) per share computation:
Anti-dilutive securities excluded (shares)	443,169	655,700	473,149	776,710
RSUs and PSUs
Diluted earnings (loss) per share computation:
Anti-dilutive securities excluded (shares)	1,202,367	8,959	1,057,057	4,504

Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent, Per Basic Share

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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