Stockholders' Equity (Reclassification From Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ 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
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	[1]	$ 730,599		$ 674,715		$ 677,215		$ 477,279		$ 480,580	[2]	$ 792,833	[2]	$ 804,113	[2]	$ 816,452	[2]
Income tax benefit		$ 19,514	[1],[3]	$ (12,565)	[1],[3]	$ (15,322)	[1],[3]	$ (12,943)	[1],[3]	$ 14,457	[1]	$ (14,941)	[1]	$ (12,498)	[1]	$ (7,165)	[1]	$ (21,316)	$ (20,147)	$ (132,061)
Net income (loss)																		(148,000)	36,734	81,631
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss from continuing operations before income taxes and income (loss) from equity method investees	[4]																		4,906	30,945
Net income from discontinued operations, net of taxes	[5]																	38,795	(10,092)	(15,566)
Income tax benefit	[6]																		1,483	11,454
Net income (loss)																		$ 38,795	(6,669)	3,925
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) [Member] | Commodity Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenues	[7]																		3,648	42,710
Cost of goods sold	[8]																		$ 1,258	$ (11,765)

[1] GPCC results prior to its disposition are classified as discontinued operations in current and prior period consolidated financial statements.

[2] The fourth quarter of 2018 includes the net gain on the sale of assets of $150.4 million related to the sale of three ethanol plants and Fleischmann’s Vinegar

[3] The fourth quarter of 2019 includes the recognition of a $25.3 million valuation allowance which impacted income tax expense.

[4] Income (loss) from continuing operations before income taxes and income (loss) from equity method investees

[5] Net income from discontinued operations, net of income taxes

[6] Income tax benefit

[7] Revenues

[8] Costs of goods sold