Capitalized Software Development Costs (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Indemnity
Total capitalized software development costs subject to amortization and the related amortization expense
Gross carrying amount	$ 68	$ 58	$ 54
Accumulated amortization	(25)	(18)	(11)
Net carrying amount	43	40	43
Amortization expense	7	7	6
Gross carrying amount, not yet subject to amortization	11	9	7
Estimated future amortization expense related to capitalized software development costs
2015	8
2016	8
2017	7
2018	4
2019	2
Exchange
Total capitalized software development costs subject to amortization and the related amortization expense
Gross carrying amount, not yet subject to amortization	$ 4