Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 648	$ 653	$ 683	$ 689	$ 703	$ 743	$ 728	$ 711	$ 2,673		$ 2,885		$ 2,785
Profit before income taxes	129	153	150	187	166	197	208	182	619		753		694
Profit	$ 114	$ 109	$ 104	$ 133	$ 108	$ 148	$ 148	$ 131	$ 460	[1]	$ 535	[1]	$ 513	[1]

[1] Profit attributable to Caterpillar Financial Services Corporation.