Property, Software and Equipment |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2017 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Property, Plant and Equipment [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Property, Software and Equipment | Property, Software and Equipment Property, software and equipment consist of the following as of December 31 ($ in millions):
As of December 31, 2017 and 2016, the Company had assets acquired under capital leases included above of $5 million and $5 million, net of accumulated amortization of $5 million and $4 million, respectively. Amortization on assets under capital leases charged to expense is included in depreciation expense. Depreciation expense for the years ended December 31, 2017, 2016 and 2015 was $161 million, $101 million and $78 million, respectively. |
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