Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Profit of consolidated companies	$ 76	$ 115	$ 171	$ 232
Other comprehensive income (loss), net of tax:
Foreign currency translation, net of tax (expense)/benefit	(262)	161	(191)	241
Derivative financial instruments:
Gains (losses) deferred, net of tax (expense)/benefit	99	(15)	73	(27)
(Gains) losses reclassified to earnings, net of tax expense/(benefit)	(96)	16	(76)	30
Available-for-sale securities
Gains (losses) deferred, net of tax (expense)/benefit	0	1	0	1
(Gains) losses reclassified to earnings, net of tax expense/(benefit)	0	0	0	0
Total Other comprehensive income (loss), net of tax	(259)	163	(194)	245
Comprehensive income (loss)	(183)	278	(23)	477
Less: Comprehensive income (loss) attributable to the noncontrolling interests	(3)	4	7	6
Comprehensive income (loss) attributable to Caterpillar Financial Services Corporation	$ (180)	$ 274	$ (30)	$ 471