REVENUES (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Revenue, Initial Application Period Cumulative Effect Transition [Table Text Block]

The impact on our Consolidated Income Statement and Balance Sheet is as follows (in thousands):

	Year Ended December 31, 2018
Income Statement	As Reported		Balance Without Adoption of Topic 606		Effect of Change Increase/(Decrease)
Commodity sales	$	11,395,642	$	11,460,913	$	(65,271	)
Services revenue	$	1,197,554	$	2,712,256	$	(1,514,702	)
Cost of sales and fuel (exclusive of depreciation and operating costs)	$	9,422,708	$	11,006,278	$	(1,583,570	)
Depreciation and amortization	$	428,557	$	427,976	$	581
Income taxes	$	362,903	$	362,210	$	693
Net income	$	1,155,032	$	1,152,709	$	2,323
Net income attributable to noncontrolling interests	$	3,329	$	3,322	$	7
Net income attributable to ONEOK	$	1,151,703	$	1,149,387	$	2,316

	December 31, 2018
Balance Sheet	As Reported		Balance Without Adoption of Topic 606		Effect of Change Increase/(Decrease)
Accounts receivable, net	$	818,958	$	956,523	$	(137,565	)
Natural gas and natural gas liquids in storage	$	296,667	$	301,555	$	(4,888	)
Other current assets	$	100,808	$	99,579	$	1,229
Property, plant and equipment	$	18,030,963	$	18,006,653	$	24,310
Accumulated depreciation and amortization	$	3,264,312	$	3,262,359	$	1,953
Other assets	$	130,096	$	125,606	$	4,490
Accounts payable	$	1,118,102	$	1,255,667	$	(137,565	)
Other current liabilities	$	211,110	$	209,258	$	1,852
Deferred income taxes	$	219,731	$	218,536	$	1,195
Other deferred credits	$	450,627	$	434,508	$	16,119
Retained earnings/paid-in capital	$	7,615,138	$	7,611,116	$	4,022

Contract with Customer, Asset and Liability [Table Text Block]

The following tables set forth the changes in our contract asset and contract liability balances for the year ended December 31, 2018:

Contract Assets	(Millions of dollars)
Balance at January 1, 2018 (a)	$	6.4
Amounts invoiced in excess of revenue recognized	(0.9		)
Net additions	0.7
Balance at December 31, 2018 (b)	$	6.2

(a) - Balance includes $0.9 million of current assets.

(b) - Contract assets of $1.7 million and $4.5 million are included in other current assets and other assets, respectively, in our Consolidated Balance Sheet.

Contract Liabilities	(Millions of dollars)
Balance at January 1, 2018 (a)	$	33.3
Revenue recognized included in beginning balance	(19.5		)
Net additions	17.9
Balance at December 31, 2018 (b)	$	31.7

(a) - Balance includes $19.5 million of current liabilities.

(b) - Contract liabilities of $15.6 million and $16.1 million are included in other current liabilities and other deferred credits, respectively, in our Consolidated Balance Sheet.

Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]

The following table presents aggregate value allocated to unsatisfied performance obligations as of December 31, 2018, and the amounts we expect to recognize in revenue in future periods, related primarily to firm transportation and storage contracts with remaining contract terms ranging from one month to 25 years:

Expected Period of Recognition in Revenue	(Millions of dollars)
2019	$	308.6
2020	256.1
2021	242.4
2022	192.7
2023 and beyond	892.0
Total estimated transaction price allocated to unsatisfied performance obligations	$	1,891.8