Inventories (Details) $ in Thousands, bu in Millions	Jun. 30, 2018 USD ($) bu	Dec. 31, 2017 USD ($) bu	Jun. 30, 2017 USD ($) bu
Inventory, Net [Abstract]
Grain	$ 385,118	$ 505,217	$ 373,863
Ethanol and co-products	22,828	11,003	14,041
Plant nutrients and cob products	82,230	126,962	69,365
Retail merchandise	0	0	906
Railcar repair parts	5,435	5,521	5,030
Total inventories	$ 495,611	$ 648,703	$ 463,205
Bushels of grain held in storage and excluded from inventory calculations \| bu	0.1	1.0	0.8

Grain Held in Storage, Excluded from Inventory Calculations

No definition available.

Name:	ande_GrainHeldinStorageExcludedfromInventoryCalculations
Namespace Prefix:	ande_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	instant

- Definition

Railcar repair parts inventory.

+ References

No definition available.

+ Details

Name:	ande_RailcarRepairPartsInventory
Namespace Prefix:	ande_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of merchandise or supplies held which are related to plants and animals.

+ References

+ Details

Name:	us-gaap_AgriculturalRelatedInventory
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of products that are used in the growth of plant goods (examples would include seeds, soil, fertilizers and other products).

+ References

+ Details

Name:	us-gaap_AgriculturalRelatedInventoryPlantMaterial
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

+ References

+ Details

Name:	us-gaap_EnergyRelatedInventory
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

+ Details

Name:	us-gaap_InventoryNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_InventoryNetAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of merchandise inventory purchased by a retailer, wholesaler or distributor and held for future sale.

+ References

+ Details

Name:	us-gaap_RetailRelatedInventoryMerchandise
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant