Derivatives (Volume of Contracts Outstanding) (Details) gal in Thousands, bu in Thousands, T in Thousands	Mar. 31, 2022 bu	Mar. 31, 2022 gal	Mar. 31, 2022 T	Dec. 31, 2021 bu	Dec. 31, 2021 gal	Dec. 31, 2021 T	Mar. 31, 2021 bu	Mar. 31, 2021 gal	Mar. 31, 2021 T
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	1,447,086	300,986	4,610	1,319,055	341,763	3,258	1,375,001	312,361	2,160
Non-exchange Traded
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	1,013,116	239,078	4,063	961,715	208,539	2,905	973,587	202,066	1,895
Non-exchange Traded | Corn
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	722,719	0	0	685,681	0	0	745,248	0	0
Non-exchange Traded | Soybeans
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	133,043	0	0	77,592	0	0	64,698	0	0
Non-exchange Traded | Wheat
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	102,690	0	0	109,547	0	0	110,930	0	0
Non-exchange Traded | Oats
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	45,967	0	0	31,627	0	0	48,066	0	0
Non-exchange Traded | Ethanol
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	0	214,513	0	0	192,447	0	0	200,232	0
Non-exchange Traded | Dried distillers grain
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	0	0	435	0	0	507	0	0	409
Non-exchange Traded | Soybean meal
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	0	0	550	0	0	544	0	0	383
Non-exchange Traded | Other
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	8,697	24,565	3,078	57,268	16,092	1,854	4,645	1,834	1,103
Exchange Traded
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	433,970	61,908	547	357,340	133,224	353	401,414	110,295	265
Exchange Traded | Corn
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	267,135	0	0	226,215	0	0	262,920	0	0
Exchange Traded | Soybeans
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	86,410	0	0	64,730	0	0	62,020	0	0
Exchange Traded | Wheat
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	78,500	0	0	65,020	0	0	76,164	0	0
Exchange Traded | Oats
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	1,815	0	0	1,300	0	0	310	0	0
Exchange Traded | Ethanol
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	0	47,082	0	0	100,884	0	0	96,978	0
Exchange Traded | Propane
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	0	13,356	0	0	31,542	0	0	12,894	0
Exchange Traded | Other
Amounts of quantities outstanding included in commodity derivative contracts
Nonmonetary notional amount	110	1,470	547	75	798	353	0	423	265