Property, plant and equipment and assets held for lease (Tables)

3 Months Ended

Mar. 31, 2017

Schedule of depreciation expense

A summary of depreciation expense for the first quarters of 2017 and 2016 follows (in millions).

	First Quarter
	2017		2016
Insurance and other	$	542	$	493
Railroad, utilities and energy		1,175		1,141
Finance and financial products		159		152
	$	1,876	$	1,786

Insurance and Other [Member]

Schedule of property, plant and equipment

A summary of property, plant and equipment of our insurance and other businesses follows (in millions).

	Ranges of estimated useful life		March 31, 2017			December 31, 2016
Land		—	$	2,133		$	2,108
Buildings and improvements		5 – 40 years		8,461			8,360
Machinery and equipment		3 – 25 years		20,983			20,463
Furniture, fixtures and other		2 – 15 years		4,214			4,080
				35,791			35,011
Accumulated depreciation				(16,146	)		(15,686	)
			$	19,645		$	19,325

Railroad, Utilities and Energy [Member]

Schedule of property, plant and equipment

A summary of property, plant and equipment of our railroad and our utilities and energy businesses follows (in millions).

	Ranges of estimated useful life		March 31, 2017		December 31, 2016
Railroad:
Land		—	$	6,073	$	6,063
Track structure and other roadway		7 – 100 years		49,917		48,277
Locomotives, freight cars and other equipment		6 – 41 years		12,172		12,075
Construction in progress		—		810		965
				68,972		67,380
Accumulated depreciation				(7,583)		(6,130)
				61,389		61,250
Utilities and energy:
Utility generation, transmission and distribution systems		5 – 80 years		71,308		71,536
Interstate natural gas pipeline assets		3 – 80 years		6,944		6,942
Independent power plants and other assets		3 – 30 years		6,937		6,596
Construction in progress		—		2,350		2,098
				87,539		87,172
Accumulated depreciation				(24,651)		(24,663)
				62,888		62,509
			$	124,277	$	123,759

Finance and Financial Products [Member]

Schedule of property, plant and equipment

Assets held for lease and property, plant and equipment of our finance and financial products businesses are summarized below (in millions).

	Ranges of estimated useful life		March 31, 2017			December 31, 2016
Assets held for lease		5 – 35 years	$	11,993		$	11,902
Land		—		224			224
Buildings, machinery and other		3 – 50 years		1,335			1,302
				13,552			13,428
Accumulated depreciation				(3,829	)		(3,739	)
			$	9,723		$	9,689