Provision for Income Taxes (Tables)

12 Months Ended

Dec. 31, 2011

Provision for Income Taxes [Abstract]

Our federal and state income tax provision is summarized below:

	For Year Ended December 31,
	2011			2010			2009
Current:
Federal	$	(4.0	)	$	2.2		$	7.9
State		18.9			16.0			11.9
Foreign		0.2			--			1.0
Total current		15.1			18.2			20.8
Deferred:
Federal		11.5			5.3			4.8
State		0.8			2.9			(0.3	)
Foreign		(0.2	)		(0.3	)		--
Total deferred		12.1			7.9			4.5
Total provision for income taxes	$	27.2		$	26.1		$	25.3

Reconciliation of Provision for Income Taxes

A reconciliation of the provision for income taxes with amounts determined by applying the statutory U.S. federal income tax rate to income before income taxes is as follows:

	For Year Ended December 31,
	2011			2010			2009
Pre-Tax Net Book Income (“NBI”)	$	2,115.5		$	1,409.8		$	1,165.6

Texas Margin Tax (1)	$	19.1		$	18.3		$	10.1
State income taxes (net of federal benefit)		0.5			0.4			1.3
Federal income taxes computed by applying the federal statutory rate to NBI of corporate entities		5.0			8.0			8.3
Valuation allowance		(0.2	)		--			(1.7	)
Expiration of tax net operating loss		0.2			--			1.7
Other permanent differences		2.6			(0.6	)		5.6
Provision for income taxes	$	27.2		$	26.1		$	25.3

Effective income tax rate		1.3%			1.9%			2.2%

(1) Although the Texas Margin Tax is not considered a state income tax, it has the characteristics of an income tax since it is determined by applying a tax rate to a base that considers our Texas-sourced revenues and expenses.

Components of Deferred Tax Assets and Liabilities

Significant components of deferred tax assets and deferred tax liabilities as of December 31, 2011 and 2010 are as follows:

	At December 31,
	2011		2010
Deferred tax assets:
Net operating loss carryovers (1)	$	17.8	$	23.4
Employee benefit plans		3.0		3.1
Deferred revenue		1.5		1.2
Equity investment in partnerships		0.9		0.9
AROs		0.1		0.1
Accruals		1.6		1.4
Total deferred tax assets		24.9		30.1
Valuation allowance (2)		2.0		2.2
Net deferred tax assets		22.9		27.9
Less: Deferred tax liabilities:
Property, plant and equipment		112.1		103.9
Total deferred tax liabilities		112.1		103.9
Total net deferred tax liabilities	$	89.2	$	76.0

Current portion of total net deferred tax assets	$	2.0	$	2.0
Long-term portion of total net deferred tax liabilities	$	91.2	$	78.0

(1) These losses expire in various years between 2012 and 2028 and are subject to limitations on their utilization. (2) We record a valuation allowance to reduce our deferred tax assets to the amount of future benefit that is more likely than not to be realized.