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								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic earnings (loss) per share computation:
Income (loss) from continuing operations	$ (294,651)	$ (79,393)	$ (64,863)	$ (61,827)	$ (263,301)	$ (26,648)	$ (42,016)	$ (265)	$ (500,734)	$ (332,230)	$ 47,422
Net loss attributable to non-controlling interest									862	458	0
Income (loss) from continuing operations attributable to Dean Foods Company									$ (499,872)	$ (331,772)	$ 47,422
Average common shares - basic (shares)									91,777,119	91,327,846	90,899,284
Basic earnings (loss) per share from continuing operations (USD per share)									$ (5.45)	$ (3.63)	$ 0.52
Diluted earnings (loss) per share computation:
Income (loss) from continuing operations	$ (294,651)	$ (79,393)	$ (64,863)	$ (61,827)	$ (263,301)	$ (26,648)	$ (42,016)	$ (265)	$ (500,734)	$ (332,230)	$ 47,422
Net loss attributable to non-controlling interest									862	458	0
Income (loss) from continuing operations attributable to Dean Foods Company									$ (499,872)	$ (331,772)	$ 47,422
Stock option conversion (shares)									0	0	119,284
RSUs and PSUs (shares)									0	0	255,426
Average common shares - diluted (shares)									91,777,119	91,327,846	91,273,994
Diluted earnings (loss) per share from continuing operations attributable to Dean Foods Company (USD per share)									$ (5.45)	$ (3.63)	$ 0.52
Common Stock
Diluted earnings (loss) per share computation:
Anti-dilutive options excluded (shares)									183,685	436,473	880,541
Stock Units
Diluted earnings (loss) per share computation:
Anti-dilutive options excluded (shares)									1,541,276	1,086,206	442,047