Income Tax Expense (Tables)

12 Months Ended

Dec. 31, 2014

Income Tax Expense [Abstract]

Income Tax Expense [Table Text Block]

Income Tax Expense
Year Ended December 31	2014			2013			2012
Millions
Current Tax Expense
Federal (a)	$1.1			—			—
State (a)	2.9			$0.1			$0.5
Total Current Tax Expense	4.0			0.1			0.5
Deferred Tax Expense
Federal	25.3			22.9			37.0
State	8.2			6.5			1.4
Investment Tax Credit Amortization	(0.8		)	(0.8		)	(0.9		)
Total Deferred Tax Expense	32.7			28.6			37.5
Total Income Tax Expense		$36.7			$28.7			$38.0

(a) For the years ended December 31, 2014, 2013, and 2012, the federal and state current tax expense was minimal due to NOLs which resulted from the bonus depreciation provisions of the Tax Increase Prevention Act of 2014 and the American Taxpayer Relief Act of 2012. The federal and state NOLs will be carried forward to offset future taxable income. The year ended 2014 includes the resolution of an IRS examination for the tax years 2005-2009 and the impacts of initiatives implemented on the 2013 federal and state tax returns to utilize tax carryforwards that may have expired.

Reconciliation of Taxes from Federal Statutory Rate to Total Income Tax Expense [Table Text Block]

Reconciliation of Taxes from Federal Statutory
Rate to Total Income Tax Expense
Year Ended December 31	2014			2013			2012
Millions
Income Before Non-Controlling Interest and Income Taxes		$162.2			$133.4			$135.1
Statutory Federal Income Tax Rate	35		%	35		%	35		%
Income Taxes Computed at 35 percent Statutory Federal Rate		$56.8			$46.7			$47.3
Increase (Decrease) in Tax Due to:
State Income Taxes – Net of Federal Income Tax Benefit	7.2			4.3			1.2
Regulatory Differences for Utility Plant	(3.5		)	(2.2		)	(2.2		)
Production Tax Credits	(23.7		)	(19.2		)	(7.6		)
Other	(0.1		)	(0.9		)	(0.7		)
Total Income Tax Expense		$36.7			$28.7			$38.0

Deferred Tax Assets and Liabilities [Table Text Block]

Deferred Tax Assets and Liabilities
As of December 31	2014			2013
Millions
Deferred Tax Assets
Employee Benefits and Compensation		$102.2			$66.3
Property Related	102.7			82.2
NOL Carryforwards	156.5			112.8
Tax Credit Carryforwards	95.7			55.1
Power Purchase Agreements	51.8			—
Other	17.0			16.9
Gross Deferred Tax Assets	525.9			333.3
Deferred Tax Asset Valuation Allowance	(22.1		)	(8.0		)
Total Deferred Tax Assets		$503.8			$325.3
Deferred Tax Liabilities
Property Related		$848.8			$656.2
Regulatory Asset for Benefit Obligations	89.9			58.7
Unamortized Investment Tax Credits	10.3			11.1
Partnership Basis Differences	41.9			36.7
Other	16.1			22.7
Total Deferred Tax Liabilities		$1,007.0			$785.4
Net Deferred Income Taxes		$503.2			$460.1
Recorded as:
Net Current Deferred Tax Assets		$7.5		$19.0
Net Long-Term Deferred Tax Liabilities	510.7			479.1
Net Deferred Income Taxes		$503.2			$460.1

NOL and Tax Credit Carryforwards
As of December 31	2014	2013
Millions
Federal NOL Carryforwards (a)	$413.7		$279.8
Federal Tax Credit Carryforwards	$59.3	$35.5
State NOL Carryforwards (a)	$184.7	$156.3
State Tax Credit Carryforwards (b)	$14.7	$11.9

NOL and Tax Credit Carryforwards [Table Text Block]

NOL and Tax Credit Carryforwards
As of December 31	2014	2013
Millions
Federal NOL Carryforwards (a)	$413.7		$279.8
Federal Tax Credit Carryforwards	$59.3	$35.5
State NOL Carryforwards (a)	$184.7	$156.3
State Tax Credit Carryforwards (b)	$14.7	$11.9

(a) Pretax amounts.

(b) Net of a $21.7 million valuation allowance as of December 31, 2014 ($7.7 million as of December 31, 2013).

Gross Unrecognized Income Tax Benefits [Table Text Block]

Gross Unrecognized Income Tax Benefits	2014			2013			2012
Millions
Balance at January 1		$1.2			$2.7			$11.4
Additions for Tax Positions Related to the Current Year	—			0.1			—
Additions for Tax Positions Related to Prior Years	1.0			1.3			—
Reductions for Tax Positions Related to Prior Years	—			—			(8.7		)
Reductions for Settlements	—			(2.9		)	—
Lapse of Statute	(0.2		)	—			—
Balance as of December 31		$2.0			$1.2			$2.7