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Debt instrument applicable conversion price percentage

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Debt Instrument, Exchange Amount

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Interest coverage ratio.

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Long Term Debt Prepayment Fees

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Number Of Ethanol Plants

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Special Annual Payments From Available Free Cash Flow, Percentage,

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Term Debt To Total Term Capitalization

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Aggregate dividends paid during the period for each share of common stock outstanding.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The price per share of the conversion feature embedded in the debt instrument.

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

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Description of any adjustments made to the stated rate to determine the effective rate.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of the required periodic payments applied to principal.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Debt (Narrative - Corporate Activities) (Details)	3 Months Ended		6 Months Ended		12 Months Ended
Debt (Narrative - Corporate Activities) (Details)	Jun. 30, 2018 USD ($) $ / shares property shares	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) $ / shares property shares	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) shares	Aug. 29, 2017 USD ($)
Debt Instrument [Line Items]
Cash payment for conversion of 3.25% convertible notes due 2018				$ 8,523,000
Interest expense	$ 22,021,000	$ 19,430,000	$ 44,149,000	37,926,000
Restricted cash	15,863,000	$ 59,334,000	15,863,000	$ 59,334,000	$ 45,709,000
$170.0 Million Convertible Notes [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 170,000,000		$ 170,000,000
Interest rate, stated percentage	4.125%		4.125%
Common stock, dividends per share, cash paid per share \| $ / shares			$ 0.12
Common stock for conversion, shares \| shares			35.7143
Debt conversion amount			$ 1,000
Debt conversion price \| $ / shares	$ 28.00		$ 28.00
Conversion price percentage			140.00%
Principal amount of notes, percentage			100.00%
$120.0 Million Convertible Notes [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 120,000,000		$ 120,000,000
Interest rate, stated percentage	3.25%		3.25%
Common stock, dividends per share, cash paid per share \| $ / shares			$ 0.04
Common stock for conversion, shares \| shares			50.6481
Debt conversion amount			$ 1,000
Debt conversion price \| $ / shares	$ 19.74		$ 19.74
Conversion price percentage			140.00%
Principal amount of notes, percentage			100.00%
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Prepayment fees			1.00%
Prepayment fee required in paid within term			18 months
Debt Instrument, Periodic Payment, Principal			$ 1,250,000
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Term Loan [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage			5.50%
Interest rate, basis for effective rate			LIBOR plus a margin of 5.50%.
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Term Loan [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Interest rate, basis spread on variable rate, percentage			4.50%
Interest rate, basis for effective rate			base rate plus a margin of 4.50%
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Term Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest coverage ratio	1.25		1.25
Special annual payments from available free cash flow, percentage			50.00%
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Term Loan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Term debt to total term capitalization			55.00%
Special annual payments from available free cash flow, percentage			75.00%
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Green Plains Processing & Fleischmanns Vinegar Company [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000,000		$ 500,000,000
Long-term Debt, Gross						$ 405,000,000
$500.0 Million Term Loan [Member] \| Corporate Activities [Member] \| Green Plains Processing & Fleischmanns Vinegar Company [Member] \| Term Loan [Member] \| Collateral Pledged [Member]
Debt Instrument [Line Items]
Number of ethanol plants \| property	17		17
Convertible Senior Notes 3.25% [Member] \| Corporate Activities [Member] \| Convertible Notes [Member]
Debt Instrument [Line Items]
Outstanding note payable	$ 63,700,000		$ 63,700,000
Common stock for conversion, shares \| shares	50				2,783,725
Debt conversion amount	$ 1,000
Debt instrument, exchange amount					$ 56,300,000