SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Schedule of significant noncash transactions

Significant noncash transactions were:

(Millions)	2013		2012		2011
Construction costs funded through accounts payable	$	108.5	$	92.4	$	58.6
Portion of Westwood sale financed with note receivable (1)	—		4.0		—
Equity issued for stock-based compensation plans	16.3		—		10.6
Equity issued for employee stock ownership plan	14.3		—		5.2
Equity issued for reinvested dividends	12.0		—		5.4
Contingent consideration related to the acquisition of Compass Energy Services (2)	7.8		—		—

⁽¹⁾   See Note 4, Discontinued Operations, for more information.

⁽²⁾ See Note 3, Acquisitions, for more information on the contingent consideration.

Schedule of annual utility composite depreciation rates

Annual utility composite depreciation rates are shown below:

Annual Utility Composite Depreciation Rates	2013		2012		2011
MERC (1)	1.88	%	3.07	%	3.10	%
MGU (2)	1.93	%	2.71	%	2.73	%
NSG	2.44	%	2.43	%	2.42	%
PGL	3.19	%	3.16	%	3.18	%
UPPCO	3.29	%	3.31	%	3.33	%
WPS – Electric	2.79	%	2.87	%	2.88	%
WPS – Natural gas	2.19	%	2.21	%	2.22	%

⁽¹⁾ The 2013 depreciation rate reflects the impact of a new depreciation study approved by the MPUC in July 2013. The rates were effective retroactive to January 2012. An approximate $2 million reduction in depreciation expense was recorded in 2013 related to the 2012 impact.

⁽²⁾   The 2013 depreciation rate includes the impact of a $2.5 million reduction in depreciation expense that was recorded in the first quarter of 2013 as a result of the Michigan Court of Appeals order reversing the MPSC's previously ordered disallowance associated with the early retirement of certain MGU assets in 2010.

Schedule of total AFUDC

Total AFUDC was as follows for the years ended December 31:

	2013		2012		2011
Allowance for equity funds used during construction	$	10.8	$	2.9	$	0.7
Allowance for borrowed funds used during construction	4.1		1.0		0.3