Revenue (Impact of New Revenue Guidance on Financial Statements) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Balance Sheet
Cash and cash equivalents and restricted cash	$ 16,820		$ 16,820
Accounts receivable, net	206,380	$ 196,192	206,380	$ 196,192	$ 183,238
Inventories	490,331	475,602	490,331	475,602	648,703
Commodity derivative assets - current	76,861	45,202	76,861	45,202	30,702
Other current assets	87,901		87,901
Other noncurrent assets	374,044	363,604	374,044	363,604	355,023
Rail Group assets leased to others, net	464,776	377,393	464,776	377,393	423,443
Property, plant and equipment, net	434,505	419,348	434,505	419,348	384,677
Total assets	2,151,618	1,964,160	2,151,618	1,964,160	2,162,354
Short-term debt and current maturities of long-term debt	147,677		147,677
Commodity derivative liabilities - current	413,331		413,331
Commodity derivative liabilities - current	91,403	38,578	91,403	38,578	29,651
Customer prepayments and deferred revenue	38,242	29,520	38,242	29,520	59,710
Commodity derivative liabilities - noncurrent and Other long-term liabilities	33,163		33,163
Employee benefit plan obligations	25,356	36,356	25,356	36,356	26,716
Long-term debt, less current maturities	437,280	371,315	437,280	371,315	418,339
Deferred income taxes	122,523		122,523
Total liabilities	1,308,975	1,214,349	1,308,975	1,214,349	1,339,455
Retained earnings	628,676	568,438	628,676	568,438	633,496
Common shares, additional paid-in-capital, treasury shares, accumulated other comprehensive loss and noncontrolling interests	213,967		213,967
Total equity	842,643	749,811	842,643	749,811	822,899	$ 790,697
Total liabilities and equity	2,151,618	1,964,160	2,151,618	1,964,160	$ 2,162,354
Income Statement Related Disclosures [Abstract]
Sales and merchandising revenues	685,579	836,595	2,232,720	2,682,273
Cost of sales and merchandising revenues	631,715	766,924	2,024,677	2,448,310
Gross profit	53,864	69,671	208,043	233,963
Operating, administrative and general expenses	65,986	68,153	190,096	219,242
Asset impairment	0	0	6,272	0
Interest expense	5,176	5,384	20,000	17,472
Equity in earnings (loss) of affiliates, net	7,225	3,586	20,601	8,093
Other income, net	6,434	5,285	10,949	17,028
Income (loss) before income taxes	(3,639)	5,005	23,225	(19,630)
Income tax provision (benefit)	(1,764)	2,389	5,668	7,505
Net income (loss)	(1,875)	2,616	17,557	(27,135)
Net income (loss) attributable to the noncontrolling interests	223	83	(175)	73
Net income attributable to The Andersons, Inc.	(2,098)	$ 2,533	17,732	$ (27,208)
ASC 606 Impact | Revenues under ASC 606
Balance Sheet
Cash and cash equivalents and restricted cash	0		0
Accounts receivable, net	0		0
Inventories	178		178
Commodity derivative assets - current	0		0
Other current assets	(268)		(268)
Other noncurrent assets	0		0
Rail Group assets leased to others, net	(23,337)		(23,337)
Property, plant and equipment, net	0		0
Total assets	(23,427)		(23,427)
Short-term debt and current maturities of long-term debt	(3,772)		(3,772)
Commodity derivative liabilities - current	0		0
Commodity derivative liabilities - current	0		0
Customer prepayments and deferred revenue	0		0
Commodity derivative liabilities - noncurrent and Other long-term liabilities	0		0
Employee benefit plan obligations	0		0
Long-term debt, less current maturities	(31,018)		(31,018)
Deferred income taxes	2,869		2,869
Total liabilities	(31,921)		(31,921)
Retained earnings	8,494		8,494
Common shares, additional paid-in-capital, treasury shares, accumulated other comprehensive loss and noncontrolling interests	0		0
Total equity	8,494		8,494
Total liabilities and equity	(23,427)		(23,427)
Income Statement Related Disclosures [Abstract]
Sales and merchandising revenues	173,183		522,648
Cost of sales and merchandising revenues	173,706		524,121
Gross profit	(523)		(1,473)
Operating, administrative and general expenses	0		0
Asset impairment	0		0
Interest expense	(387)		(1,185)
Equity in earnings (loss) of affiliates, net	0		0
Other income, net	0		0
Income (loss) before income taxes	(136)		(288)
Income tax provision (benefit)	(34)		(72)
Net income (loss)	(102)		(216)
Net income (loss) attributable to the noncontrolling interests	0		0
Net income attributable to The Andersons, Inc.	(102)		(216)
Pro forma as if the previous accounting guidance was in effect
Balance Sheet
Cash and cash equivalents and restricted cash	16,820		16,820
Accounts receivable, net	206,380		206,380
Inventories	490,509		490,509
Commodity derivative assets - current	76,861		76,861
Other current assets	87,633		87,633
Other noncurrent assets	374,044		374,044
Rail Group assets leased to others, net	441,439		441,439
Property, plant and equipment, net	434,505		434,505
Total assets	2,128,191		2,128,191
Short-term debt and current maturities of long-term debt	143,905		143,905
Commodity derivative liabilities - current	413,331		413,331
Commodity derivative liabilities - current	91,403		91,403
Customer prepayments and deferred revenue	38,242		38,242
Commodity derivative liabilities - noncurrent and Other long-term liabilities	33,163		33,163
Employee benefit plan obligations	25,356		25,356
Long-term debt, less current maturities	406,262		406,262
Deferred income taxes	125,392		125,392
Total liabilities	1,277,054		1,277,054
Retained earnings	637,170		637,170
Common shares, additional paid-in-capital, treasury shares, accumulated other comprehensive loss and noncontrolling interests	213,967		213,967
Total equity	851,137		851,137
Total liabilities and equity	2,128,191		2,128,191
Income Statement Related Disclosures [Abstract]
Sales and merchandising revenues	858,762		2,755,368
Cost of sales and merchandising revenues	805,421		2,548,798
Gross profit	53,341		206,570
Operating, administrative and general expenses	65,986		190,096
Asset impairment	0		6,272
Interest expense	4,789		(18,815)
Equity in earnings (loss) of affiliates, net	7,225		20,601
Other income, net	6,434		10,949
Income (loss) before income taxes	(3,775)		22,937
Income tax provision (benefit)	(1,798)		5,596
Net income (loss)	(1,977)		17,341
Net income (loss) attributable to the noncontrolling interests	223		(175)
Net income attributable to The Andersons, Inc.	(2,200)		17,516
Pro forma as if the previous accounting guidance was in effect | Revenues under ASC 606
Income Statement Related Disclosures [Abstract]
Sales and merchandising revenues	$ 170,400		$ 515,400