Property, Plant, and Equipment (Tables)

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

PP&E by Classification, Summary of Depreciation and Amortization

The following is a summary of Depreciation and amortization expense for DTE Energy:

	2019		2018		2017
	(In millions)
Property, plant, and equipment	$	997	$	878	$	829
Regulatory assets and liabilities	227		212		165
Intangible assets	33		27		29
Other	6		7		7
	$	1,263	$	1,124	$	1,030

The following is a summary of Depreciation and amortization expense for DTE Electric:

	2019		2018		2017
	(In millions)
Property, plant, and equipment	$	748	$	652	$	615
Regulatory assets and liabilities	193		179		133
Other	5		5		5
	$	946	$	836	$	753

The following is a summary of Property, plant, and equipment by classification as of December 31:

	2019			2018
Property, plant, and equipment	(In millions)
DTE Electric
Generation	$	12,028		$	11,027
Distribution	9,715			9,153
Other	2,536			2,567
Total DTE Electric	24,279			22,747
DTE Gas
Distribution	4,164			3,823
Storage	570			548
Transmission and other	1,244			1,204
Total DTE Gas	5,978			5,575
Non-utility and other
Gas Storage and Pipelines	3,524			2,307
Power and Industrial Projects	1,108			1,070
Other	183			111
Non-utility and other	4,815			3,488
Total DTE Energy	35,072			31,810
Accumulated depreciation and amortization
DTE Electric
Generation	(3,460		)	(3,609		)
Distribution	(2,553		)	(2,974		)
Other	(693		)	(727		)
Total DTE Electric	(6,706		)	(7,310		)
DTE Gas
Distribution	(1,334		)	(1,283		)
Storage	(172		)	(165		)
Transmission and other	(409		)	(404		)
Total DTE Gas	(1,915		)	(1,852		)
Non-utility and other
Gas Storage and Pipelines	(459		)	(390		)
Power and Industrial Projects	(604		)	(546		)
Other	(71		)	(62		)
Non-utility and other	(1,134		)	(998		)
Total DTE Energy	(9,755		)	(10,160		)
Net DTE Energy Property, plant, and equipment	$	25,317		$	21,650
Net DTE Electric Property, plant, and equipment	$	17,573		$	15,437

Property under capital leases for the Registrants as of December 31, 2018 were as follows:

	DTE Energy		DTE Electric
	(In millions)
Gross property under capital leases	$	18	$	18
Accumulated amortization of property under capital leases	$	7	$	7

Schedule of AFUDC and Interest Capitalized

The following is a summary of the Registrants' AFUDC and interest capitalized for the years ended December 31:

	DTE Energy				DTE Electric
	2019		2018		2019		2018
	(In millions)
Allowance for debt funds used during construction and interest capitalized	$	15	$	15	$	10	$	9
Allowance for equity funds used during construction	24		28		22		19
Total	$	39	$	43	$	32	$	28

Schedule of Utility Property, Plant, and Equipment

The average estimated useful life for each major class of utility Property, plant, and equipment as of December 31, 2019 follows:

	Estimated Useful Lives in Years
Utility	Generation	Distribution	Storage
DTE Electric	34	38	N/A
DTE Gas	N/A	50	56

Schedule of Capitalized Software

The following balances for capitalized software relate to DTE Energy:

	Year Ended December 31,
	2019		2018		2017
	(In millions)
Amortization expense of capitalized software	$	123	$	108	$	101
Gross carrying value of capitalized software	$	906	$	905
Accumulated amortization of capitalized software	$	520	$	534

The following balances for capitalized software relate to DTE Electric:

	Year Ended December 31,
	2019		2018		2017
	(In millions)
Amortization expense of capitalized software	$	112	$	101	$	93
Gross carrying value of capitalized software	$	811	$	799
Accumulated amortization of capitalized software	$	462	$	463