INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Provision for Income Taxes

The following table sets forth our provision for income taxes for the periods indicated:

	Years Ended December 31,
	2017		2016			2015
	(Thousands of dollars)
Current income tax provision
Federal	$	295	$	6,086		$	13,191
State	1,670		2,449			2,967
Total current income taxes from continuing operations	1,965		8,535			16,158
Deferred income tax provision
Federal	376,728		193,974			116,681
State	68,589		9,897			3,761
Total deferred income taxes from continuing operations	445,317		203,871			120,442
Total provision for income taxes from continuing operations	447,282		212,406			136,600
Discontinued operations	—		(1,250		)	2,031
Total provision for income taxes	$	447,282	$	211,156		$	138,631

Reconciliation of Income Tax Provision

The following table is a reconciliation of our income tax provision from continuing operations and excludes discontinued operations for the periods indicated:

	Years Ended December 31,
	2017			2016			2015
	(Thousands of dollars)
Income before income taxes	$	1,040,801		$	957,956		$	521,876
Less: Net income attributable to noncontrolling interests	205,678			391,460			134,218
Net income attributable to ONEOK before income taxes	835,123			566,496			387,658
Federal statutory income tax rate	35.0		%	35.0		%	35.0		%
Provision for federal income taxes	292,293			198,274			135,680
State income taxes, net of federal benefit	16,197			12,303			5,800
Deferred tax rate change, inclusive of valuation allowance	141,283			43			928
Other, net	(2,491		)	1,786			(5,808		)
Income tax provision	$	447,282		$	212,406		$	136,600

Schedule of Deferred Tax Assets and Liabilities

The following table sets forth the tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities for the periods indicated:

	December 31, 2017			December 31, 2016
Deferred tax assets	(Thousands of dollars)
Employee benefits and other accrued liabilities	$	85,355		$	118,831
Federal net operating loss	159,162			26,334
State net operating loss and benefits	73,277			39,759
Derivative instruments	30,060			32,082
Other	13,546			2,425
Total deferred tax assets	361,400			219,431
Valuation allowance for state net operating loss and tax credits
Carryforward expected to expire prior to utilization	(66,632		)	(9,430		)
Net deferred tax assets	294,768			210,001
Deferred tax liabilities
Excess of tax over book depreciation	64,508			107,249
Investment in partnerships	77,035			1,726,541
Regulatory assets	15			33
Total deferred tax liabilities	141,558			1,833,823
Net deferred tax assets (liabilities) before discontinued operations	153,210			(1,623,822		)
Discontinued operations	—			10,500
Net deferred tax assets (liabilities)	$	153,210		$	(1,613,322	)