Discontinued Operations Reconciliation of Major Classes of Profit or Loss of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	[1]	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales										$ 4,385	$ 4,465	$ 5,215
Cost of sales										3,496	3,631	4,269
Selling, general and administrative										298	222	236
Amortization										15	17	24
Restructuring										90	161	115
Other Expense										(54)	(2)	(5)
Income from discontinued operations before income taxes and equity income										432	432	566
Income tax expense on discontinued operations										(71)	(75)	(112)
Equity loss from discontinued operations, net of tax										4	0	(1)
Gain (loss) on divestiture of discontinued operations, net of tax									$ 104	0	104	318
Adjustment to prior period gain on divestiture, net of tax										0	3	0
Impairment loss										0	0	(88)
Income from discontinued operations, net of tax	$ 55	$ 107	$ 80	$ 123		$ 109	$ 104	$ 18	$ 227	365	458	683
Income from discontinued operations attributable to noncontrolling interests										31	35	46
Income from discontinued operations attributable to Delphi										334	423	637
Income from discontinued operations before income taxes attributable to Aptiv										399	491	739
Discontinued Operations, Held-for-sale or Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense of discontinued operations attributable to noncontrolling interest										$ 6	$ 7	$ 10

[1] In the fourth quarter of 2016, Aptiv recognized a pre-tax gain of $141 million on the divestiture of its Mechatronics business.