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	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic loss per share computation:
Loss from continuing operations	$ (26,648)	$ (9,973)	$ (68,929)	$ (2,085)
Net loss attributable to non-controlling interest	224	0	224	0
Loss from continuing operations attributable to Dean Foods Company	$ (26,424)	$ (9,973)	$ (68,705)	$ (2,085)
Denominator:
Average common shares	91,372,325	90,939,101	91,302,990	90,844,613
Basic loss per share from continuing operations (USD per share)	$ (0.29)	$ (0.11)	$ (0.75)	$ (0.03)
Diluted loss per share computation:
Loss from continuing operations	$ (26,648)	$ (9,973)	$ (68,929)	$ (2,085)
Net loss attributable to non-controlling interest	224	0	224	0
Loss from continuing operations attributable to Dean Foods Company	$ (26,424)	$ (9,973)	$ (68,705)	$ (2,085)
Denominator:
Average common shares — basic	91,372,325	90,939,101	91,302,990	90,844,613
Average common shares — diluted	91,372,325	90,939,101	91,302,990	90,844,613
Diluted loss per share from continuing operations (USD per share)	$ (0.29)	$ (0.11)	$ (0.75)	$ (0.03)
Stock options
Denominator:
Stock option conversion	0	0	0	0
RSUs and PSUs
Denominator:
Stock option conversion	0	0	0	0
Stock options
Denominator:
Anti-dilutive securities excluded (shares)	401,269	1,211,592	448,925	1,492,474
RSUs and PSUs
Denominator:
Anti-dilutive securities excluded (shares)	1,142,746	1,068,640	1,085,982	1,010,675

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

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Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent, Per Diluted 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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Amount after tax of income (loss) from continuing operations attributable to the parent.

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Amount after tax of income (loss) from continuing operations attributable to the noncontrolling interest.

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Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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