Asset Impairments (Notes)	12 Months Ended
Dec. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Asset Impairments	Asset Impairments We recorded impairment losses of $33.9 million, $1.3 million, and $5.9 million for certain of our operating assets in 2015, 2014 and 2013. In addition, an impairment loss of $19.0 million was recorded in 2015 for one of our affiliate investments. During 2015, GATX management made the decision to exit the majority of our marine investments within the Portfolio Management segment, including six chemical parcel tankers (the "Nordic Vessels"), certain inland marine vessels, and our 50% interest in the Cardinal Marine joint venture. As a result, the Nordic Vessels and the inland marine vessels were classified as held for sale and adjusted to the lower of their respective carrying amounts or fair value less costs to sell. Furthermore, the Cardinal Marine joint venture was evaluated to assess whether an other-than-temporary decline in the value of the investment had occurred. Based on our analysis, an aggregate impairment loss of $49.8 million was recognized. These impairments were driven by our decision to exit these investments and resulted primarily from the associated change in our expected use and holding periods for these assets. The impairment losses on the vessels of $30.8 million were included in net (loss) gains on asset dispositions, and the impairment loss on our Cardinal Marine investment of $19.0 million was included in the share of affiliates' earnings in the consolidated statement of comprehensive income. As of December 31, 2015, we have completed the sales of certain of our marine investments, as well as our 50% interest in the Cardinal Marine joint venture. In addition to the impairments of marine assets noted above, we also recorded impairment losses of $3.1 million for railcars and other operating assets designated for sale or scrapping in 2015. In 2014 and 2013, impairment losses related to certain railcars and other long-lived assets designated for sale or scrapping. For each year, impairment losses were included in net (loss) gains on asset dispositions in the consolidated statement of comprehensive income. Total assets classified as held for sale at December 31, 2015 were $106.0 million, including $103.4 million of marine investments, all of which we expect to sell in 2016.

Asset Impairments

We recorded impairment losses of $33.9 million, $1.3 million, and $5.9 million for certain of our operating assets in 2015, 2014 and 2013. In addition, an impairment loss of $19.0 million was recorded in 2015 for one of our affiliate investments.

During 2015, GATX management made the decision to exit the majority of our marine investments within the Portfolio Management segment, including six chemical parcel tankers (the "Nordic Vessels"), certain inland marine vessels, and our 50% interest in the Cardinal Marine joint venture. As a result, the Nordic Vessels and the inland marine vessels were classified as held for sale and adjusted to the lower of their respective carrying amounts or fair value less costs to sell. Furthermore, the Cardinal Marine joint venture was evaluated to assess whether an other-than-temporary decline in the value of the investment had occurred. Based on our analysis, an aggregate impairment loss of $49.8 million was recognized. These impairments were driven by our decision to exit these investments and resulted primarily from the associated change in our expected use and holding periods for these assets. The impairment losses on the vessels of $30.8 million were included in net (loss) gains on asset dispositions, and the impairment loss on our Cardinal Marine investment of $19.0 million was included in the share of affiliates' earnings in the consolidated statement of comprehensive income. As of December 31, 2015, we have completed the sales of certain of our marine investments, as well as our 50% interest in the Cardinal Marine joint venture.

In addition to the impairments of marine assets noted above, we also recorded impairment losses of $3.1 million for railcars and other operating assets designated for sale or scrapping in 2015. In 2014 and 2013, impairment losses related to certain railcars and other long-lived assets designated for sale or scrapping. For each year, impairment losses were included in net (loss) gains on asset dispositions in the consolidated statement of comprehensive income. Total assets classified as held for sale at December 31, 2015 were $106.0 million, including $103.4 million of marine investments, all of which we expect to sell in 2016.