Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Net sales	$ 1,951,230	$ 1,926,722	$ 3,931,737	$ 3,922,408
Reduction of cost of sales	1,518,446	1,459,242	3,050,450	2,992,709
Product
Disaggregation of Revenue [Line Items]
Net sales	1,787,290	1,903,138	3,590,828	3,885,419
Fluid milk
Disaggregation of Revenue [Line Items]
Net sales	1,157,288	1,266,688	2,417,222	2,683,344
Ice cream
Disaggregation of Revenue [Line Items]
Net sales	321,005	324,955	560,603	580,339
Fresh cream
Disaggregation of Revenue [Line Items]
Net sales	99,816	92,911	191,766	180,782
Extended shelf life and other dairy products
Disaggregation of Revenue [Line Items]
Net sales	46,183	46,578	91,425	94,716
Cultured
Disaggregation of Revenue [Line Items]
Net sales	65,504	72,111	129,670	144,185
Other beverages
Disaggregation of Revenue [Line Items]
Net sales	66,700	72,100	137,044	147,034
Other
Disaggregation of Revenue [Line Items]
Net sales	30,794	27,795	63,098	55,019
Branded products
Disaggregation of Revenue [Line Items]
Net sales	871,269	926,351	1,763,395	1,907,596
Private label products
Disaggregation of Revenue [Line Items]
Net sales	916,021	976,787	1,827,433	1,977,823
Sales of excess raw materials
Disaggregation of Revenue [Line Items]
Net sales	122,880	0	274,682	0
Reduction of cost of sales		137,200		308,200
Sales of other bulk commodities
Disaggregation of Revenue [Line Items]
Net sales	$ 41,060	23,584	$ 66,227	36,989
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Disaggregation of Revenue [Line Items]
Net sales		137,204		308,207
Reduction of cost of sales		$ 137,204		$ 308,207