Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Estimated lives of useful depreciable assets

Operating Assets and Facilities

We state operating assets, facilities, and capitalized improvements at cost. We include assets we acquire under capital leases in operating assets, and we record the related obligations as liabilities. We depreciate operating assets and facilities over their estimated useful lives or lease terms to estimated residual values using the straight-line method. We depreciate leasehold improvements over the shorter of their useful lives or the lease term. Our estimated depreciable lives of operating assets and facilities are as follows:

Railcars	20–45 years
Locomotives	10–20 years
Buildings	40–50 years
Leasehold improvements	5–15 years
Marine vessels	30–65 years
Other equipment	5–30 years

Net gain on disposition of assets

The following table presents the net gain on asset dispositions for the years ending December 31 (in millions):

	2016			2015			2014
Net disposition gains	$	49.7		$	90.3		$	63.1
Residual sharing income	83.6			13.4			9.4
Non-remarketing net disposition gains	3.2			9.4			16.0
Asset impairment losses (1)	(38.5		)	(33.9		)	(1.3		)
Net Gain on Asset Dispositions	$	98.0		$	79.2		$	87.2