Name:	rex_ForwardPurchaseContractsQuantity
Namespace Prefix:	rex_
Data Type:	dtr:volumeItemType
Balance Type:	na
Period Type:	instant

Installment amount.

No definition available.

Name:	rex_InstallmentAmount
Namespace Prefix:	rex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Lease expiration period.

No definition available.

Name:	rex_LeaseExpirationPeriod
Namespace Prefix:	rex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Quantity of distillers grains under sales commitment.

No definition available.

Name:	rex_QuantityOfDistillersGrainsUnderSalesCommitment
Namespace Prefix:	rex_
Data Type:	dtr:massItemType
Balance Type:	na
Period Type:	instant

Quantity of ethanol under sales commitment.

No definition available.

Name:	rex_QuantityOfEthanolUnderSalesCommitment
Namespace Prefix:	rex_
Data Type:	dtr:volumeItemType
Balance Type:	na
Period Type:	instant

Quantity Of Natural Gas Under Sales Commitment

No definition available.

Name:	rex_QuantityOfNaturalGasUnderSalesCommitment
Namespace Prefix:	rex_
Data Type:	dtr:energyItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

Name:	rex_QuantityOfNonFoodGradeCornOilUnderSalesCommitments
Namespace Prefix:	rex_
Data Type:	dtr:massItemType
Balance Type:	na
Period Type:	instant

Amount of lessee's undiscounted obligation for lease payment for operating lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.9-06)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-6

Name:	us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Name:	us-gaap_MarketingExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow from the amount invested for projects in hopes of getting a future return or interest from it.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-13