Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Provision for Income Taxes

Our provision for income taxes consisted of the following for the years ended December 31 (in millions):

	2016			2015			2014
Current:
Federal	$	443		$	192		$	414
State		88			50			61
Foreign		38			36			56
		569			278			531
Deferred:
Federal		57			43			(89	)
State		17			(17	)		(33	)
Foreign		(1	)		4			4
		73			30			(118	)
Provision for income taxes	$	642		$	308		$	413

U.S. Federal Statutory Income Tax Rate Reconciled to Effective Rate

The U.S. federal statutory income tax rate is reconciled to the effective income tax rate for the years ended December 31 as follows:

	2016			2015			2014
Income tax expense at U.S. federal statutory rate		35.00	%		35.00	%		35.00	%
Federal tax credits		(3.08	)		(5.49	)		(3.21	)
Taxing authority audit settlements and other tax adjustments		(0.53	)		(2.67	)		(1.59	)
State and local income taxes, net of federal income tax benefit		3.31			3.20			1.77
Tax impact of impairments		0.80			0.23			0.46
Tax impact of divestitures		0.26			(0.34	)		(7.89	)
Tax rate differential on foreign income		(0.63	)		(0.99	)		(0.46	)
Other		0.10			0.17			(0.47	)
Provision for income taxes		35.23	%		29.11	%		23.61	%

Income Before Income Taxes Showing Domestic and Foreign Source

For financial reporting purposes, income before income taxes by source for the years ended December 31 was as follows (in millions):

	2016		2015		2014
Domestic	$	1,681	$	922	$	1,601
Foreign		141		138		150
Income before income taxes	$	1,822	$	1,060	$	1,751

Components of Net Deferred Tax Assets (Liabilities)

The components of net deferred tax assets (liabilities) at December 31 are as follows (in millions):

	2016			2015
Deferred tax assets:
Net operating loss, capital loss and tax credit carry-forwards	$	285		$	280
Landfill and environmental remediation liabilities		116			120
Miscellaneous and other reserves, net		355			373
Subtotal		756			773
Valuation allowance		(292	)		(273	)
Deferred tax liabilities:
Property and equipment		(728	)		(709	)
Goodwill and other intangibles		(1,218	)		(1,182	)
Net deferred tax liabilities	$	(1,482	)	$	(1,391	)

Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits, Including Accrued interest

A reconciliation of the beginning and ending amount of gross unrecognized tax benefits, including accrued interest is as follows (in millions):

	2016			2015			2014
Balance at January 1	$	71		$	42		$	49
Additions based on tax positions related to the current year		19			18			9
Additions based on tax positions of prior years		4			21			2
Accrued interest		2			2			1
Reductions for tax positions of prior years		(7	)		(1	)		—
Settlements		—			(3	)		(11	)
Lapse of statute of limitations		(7	)		(8	)		(8	)
Balance at December 31	$	82		$	71		$	42