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- Definition

Debt Instrument, Default, Percentage Of Principal Amount Outstanding Held

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- Definition

Debt Instrument, Redemption Price, Percentage Of Principal Amount Outstanding Remaining After Redemption

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- Definition

Debt Instrument, Variable Rate Minimum

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- Definition

Fixed charge coverage ratio.

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- Definition

Line of credit facility additional increase In maximum borrowing capacity.

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No definition available.

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Line of credit facility basis spread on variable rate.

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No definition available.

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- Definition

Percentage Required of Total Current Revolving Loan Commitments

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No definition available.

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- Definition

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

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- Definition

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

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- Definition

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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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

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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Debt - Narrative (Details) - USD ($)			3 Months Ended	9 Months Ended	12 Months Ended
Debt - Narrative (Details) - USD ($)	May 20, 2021	Apr. 12, 2021	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2021	Apr. 22, 2021	Apr. 30, 2020	Jun. 30, 2016	Jun. 02, 2016
Wells Fargo Revolver
Debt Instrument [Line Items]
Line of credit				$ 250,000,000			$ 150,000,000
Line of Credit Facility Additional Increase in Maximum Borrowing Capacity			$ 100,000,000	$ 50,000,000	$ 250,000,000
Debt instrument, variable rate minimum					0.00%
Percentage required of total current revolving loan commitments					10.00%
Amount required of total current revolving loan commitments					$ 25,000,000
Wells Fargo Revolver \| Minimum
Debt Instrument [Line Items]
LIBOR rate margin					1.50%
Fixed charge coverate ratio					1.0
Wells Fargo Revolver \| Maximum
Debt Instrument [Line Items]
LIBOR rate margin					2.00%
Fixed charge coverate ratio					1.0
REG Ralston term loan, variable interest rate of LIBOR plus 2.25%, due in October 2025
Debt Instrument [Line Items]
Face amount						$ 12,556,000
REG Capital term loan, fixed interest rate of 3.99%, due in January 2028
Debt Instrument [Line Items]
Face amount						$ 6,596,000
Stated interest rate (as a percent)			3.99%		3.99%
Senior Notes \| Senior Secured Green Bonds Due 2028
Debt Instrument [Line Items]
Face amount	$ 550,000,000
Stated interest rate (as a percent)	5.875%
Fees and offering expenses	$ 14,619,000
Default, percentage of principal amount outstanding held	25.00%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Percentage of principal amount redeemed	35.00%
Redemption price, percentage	105.875%
Percentage of principal amount outstanding remaining after redemption	65.00%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price, percentage	100.00%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Redemption price, percentage	102.938%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period Four
Debt Instrument [Line Items]
Redemption price, percentage	101.469%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period Five
Debt Instrument [Line Items]
Redemption price, percentage	100.00%
Senior Notes \| Senior Secured Green Bonds Due 2028 \| Debt Instrument, Redemption, Period Six
Debt Instrument [Line Items]
Redemption price, percentage	101.00%
Convertible Notes \| 2036 Convertible Notes
Debt Instrument [Line Items]
Face amount								$ 152,000,000	$ 152,000,000
Stated interest rate (as a percent)								4.00%	4.00%
Redemption price, percentage		100.00%