Quarterly Results of Operations (unaudited) - Summary (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	Dec. 31, 2011
Income Statement [Abstract]
Net sales	$ 1,840,021	$ 1,849,710	$ 1,843,498	$ 1,795,434	$ 1,929,480	$ 1,894,066	$ 1,951,230	$ 1,980,507	$ 7,328,663	$ 7,755,283	$ 7,795,025
Gross profit	336,158	350,341	379,480	373,753	383,394	390,597	432,784	448,503	1,439,732	1,655,278	1,818,067
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 income (loss)	(294,721)	(79,393)	(64,863)	(61,827)	(260,351)	(26,648)	(40,094)	(265)	(500,804)	(327,358)	61,588
Net loss attributable to Dean Foods Company	$ (294,643)	$ (79,254)	$ (64,471)	$ (61,574)	$ (260,117)	$ (26,424)	$ (40,094)	$ (265)	$ (499,942)	$ (326,900)	$ 61,588
Earnings (loss) per common share from continuing operations:
Basic (USD per share)	$ (3.22)	$ (0.86)	$ (0.70)	$ (0.67)	$ (2.88)	$ (0.29)	$ (0.46)	$ 0	$ (5.45)	$ (3.58)	$ 0.68
Diluted (USD per share)	$ (3.22)	$ (0.86)	$ (0.70)	$ (0.67)	$ (2.88)	$ (0.29)	$ (0.46)	$ 0	$ (5.45)	$ (3.58)	$ 0.67
Facility closing and reorganization costs, net of tax	$ 1,100	$ 2,800	$ 5,500	$ 3,200	$ 1,200	$ (2,000)	$ 51,200	$ 6,400
Goodwill impairment loss	21,500				190,700					$ 190,000		$ 2,080,000
Reorganization items	44,500								$ 44,527	$ 0	$ 0
WhiteWave Foods
Earnings (loss) per common share from continuing operations:
Impairments of plant, property and equipment	$ 144,000		$ 11,900		$ 11,500		$ 2,200