Debt (Narrative - Agribusiness And Energy Services Segment) (Details)	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Short-term notes payable and other borrowings	$ 140,808,000	$ 187,812,000
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member]
Debt Instrument [Line Items]
Minimum working capital required for compliance	$ 18,000,000
Percent Of Sum Of Total Commitment Plus Aggregate Seasonal Line Commitments	18.00%
Minimum Net Worth Required For Compliance, Percent	21.00%
Fixed charge coverage ratio	1.25
Annual leverage ratio	6.00
Maximum Capital Expenditures Per Year Under Agreement	$ 8,000,000.0
Maximum Unused Amounts For Capital Expenditures Under Agreements	8,000,000.0
Maximum Long Term Indebtedness Benchmark Under Agreement	$ 10,000,000.0
Maximum Long Term Debt Capitalization Under Agreement	40.00%
Short-term notes payable and other borrowings	$ 0
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	100,000,000.0
Additional amounts available under facility, accordion feature	75,000,000.0
Line of credit, maximum borrowing capacity	$ 225,000,000.0
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Revolving Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage	3.00%
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Revolving Credit Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage	2.00%
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Unused capacity fee, percentage	0.375%
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unused capacity fee, percentage	0.50%
Agribusiness & Energy Services [Member] \| Green Plains Grain [Member] \| Seasonal Borrowings [Member]
Debt Instrument [Line Items]
Additional amounts available under facility, accordion feature	$ 50,000,000.0
Agribusiness & Energy Services [Member] \| Green Plains Trade [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Additional amounts available under facility, accordion feature	70,000,000.0
Line of credit, maximum borrowing capacity	300,000,000.0
Minimum working capital required for compliance	$ 1,500,000
Fixed charge coverage ratio	1.15
Allowable dividends as percentage of net profit before taxes	50.00%
Undrawn availability of revolving credit facility on a pro forma basis	$ 10,000,000.0
Availability Benchmark Period Under Agreement	30 days
Unused capacity fee, percentage	0.375%
Agribusiness & Energy Services [Member] \| Green Plains Trade [Member] \| Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jul. 28, 2022
Interest rate, basis spread on variable rate, percentage	2.25%
Line of credit, maximum borrowing capacity	$ 285,000,000
Agribusiness & Energy Services [Member] \| Green Plains Trade [Member] \| First-in-last-out (FILO) Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage	3.25%
Line of credit, maximum borrowing capacity	$ 15,000,000
$100.0 Million Revolver [Member] \| Green Plains Grain [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 100,000,000.0	100,000,000.0
Debt Instrument, Maturity Date	Jun. 28, 2022
Short-term notes payable and other borrowings	$ 38,700,000	40,000,000
$30.0 Million Hedge Line [Member] \| Green Plains Commodity Management [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 30,000,000.0
Debt Instrument, Maturity Date	Apr. 30, 2023
Short-term notes payable and other borrowings	$ 21,682,000	$ 9,608,000
$30.0 Million Hedge Line [Member] \| Green Plains Commodity Management [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage	1.75%

Dividends As Percentage Of Net Profit Before Tax

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Annual leverage ratio

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Debt Instrument Credit Facility Amounts Available Accordion Feature

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Maximum Long Term Debt Capitalization Under Agreement

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Maximum Long Term Indebtness Benchmark Under Agreement

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Maximum Unused Amounts For Capital Expenditures Under Agreements

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Minimum Net Worth Required For Compliance, Percent

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Working capital - current assets less current liabilities

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Percent Of Sum Of Total Commitment Plus Aggregate Seasonal Line Commitments

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Undrawn Availability of Revolving Credit Facility On A ProForma Basis

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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