Property, Plant and Equipment

12 Months Ended

Dec. 31, 2011

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment Disclosure [Text Block]

PROPERTY, PLANT AND EQUIPMENT

Summary of property by classification as of December 31:



	2011			2010
	(In millions)
Property, Plant and Equipment
Electric Utility
Generation	$	9,785		$	9,268
Distribution	7,003			6,800
Total Electric Utility	16,788			16,068
Gas Utility
Distribution	2,561			2,460
Storage	406			395
Other	902			991
Total Gas Utility	3,869			3,846
Non-utility and other	1,884			1,660
Total	22,541			21,574
Less Accumulated Depreciation, Depletion and Amortization
Electric Utility
Generation	(3,946		)	(3,850		)
Distribution	(2,580		)	(2,568		)
Total Electric Utility	(6,526		)	(6,418		)
Gas Utility
Distribution	(1,041		)	(1,019		)
Storage	(127		)	(108		)
Other	(413		)	(512		)
Total Gas Utility	(1,581		)	(1,639		)
Non-utility and other	(688		)	(525		)
Total	(8,795		)	(8,582		)
Net Property, Plant and Equipment	$	13,746		$	12,992

AFUDC capitalized during 2011 and 2010 was approximately $10 million.

The composite depreciation rate for Detroit Edison was approximately 3.3% in 2011, 2010 and 2009. The composite depreciation rate for MichCon was 2.3% in 2011, 2.5% in 2010 and 3.1% in 2009.

The average estimated useful life for each major class of utility property, plant and equipment as of December 31, 2011 follows:

The estimated useful lives for major classes of non-utility assets and facilities ranges from 3 to 55 years.

Capitalized software costs are classified as Property, plant and equipment and the related amortization is included in Accumulated depreciation, depletion and amortization on the Consolidated Statements of Financial Position. The Company capitalizes the costs associated with computer software it develops or obtains for use in its business. The Company amortizes capitalized software costs on a straight-line basis over the expected period of benefit, ranging from 3 to 20 years.

Capitalized software costs amortization expense was $65 million in 2011 and 2010 and $66 million in 2009. The gross carrying amount and accumulated amortization of capitalized software costs at December 31, 2011 were $623 million and $300 million, respectively. The gross carrying amount and accumulated amortization of capitalized software costs at December 31, 2010 were $602 million and $252 million, respectively. Amortization expense of capitalized software costs is estimated to be approximately $64 million annually for 2012 through 2016.

Gross property under capital leases was $57 million and $153 million at December 31, 2011 and December 31, 2010, respectively. Accumulated amortization of property under capital leases was $34 million and $114 million at December 31, 2011 and December 31, 2010, respectively.

- Definition

The entire disclosure for long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software. This disclosure may include property plant and equipment accounting policies and methodology, a schedule of property, plant and equipment gross, additions, deletions, transfers and other changes, depreciation, depletion and amortization expense, net, accumulated depreciation, depletion and amortization expense and useful lives, income statement disclosures, assets held for sale and public utility disclosures.

+ References+ Details

Estimated Useful Lives in Years

Generation

Distribution

Transmission