CONDENSED CONSOLIDATING FINANCIAL STATEMENTS - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 838	$ 1,037
Investing activities
Capital expenditures for property, plant and equipment	(280)	(246)
Sales (purchases) of short-term investments - net	284	(309)
Investments in affiliates	0	0
Return of capital contributions from affiliates		0
Loans to affiliates	0	0
Repayments of loans from affiliates	0	0
Other - net	(41)	(31)
Net cash provided by (used in) investing activities	(37)	(586)
Financing activities
Proceeds from borrowings	500	832
Payments on borrowings	(486)	(543)
Proceeds from borrowings from affiliates	0	0
Payments on borrowings from affiliates	0	0
Capital contributions from affiliates	0	0
Return of capital contributions to affiliates		0
Other intercompany financing activities	0	0
Cash dividends paid	(578)	(537)
Payments of Distributions to Affiliates	0	0
Exercise of employee stock options	21	49
Repurchase of shares	(600)	(465)
Payments Related to Tax Withholding for Share-based Compensation	(23)	(21)
Other - net	(2)	(4)
Net cash provided by (used in) financing activities	(1,168)	(689)
Effect of currency on cash	62	7
Total increase (decrease) in cash	(305)	(231)
Cash at the beginning of the period	561	543
Cash at the end of the period	256	312
Guarantors [Member]
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	103	969
Investing activities
Capital expenditures for property, plant and equipment	(51)	(56)
Sales (purchases) of short-term investments - net	0	0
Investments in affiliates	0	0
Return of capital contributions from affiliates		20
Loans to affiliates	(85)	(283)
Repayments of loans from affiliates	886	287
Other - net	1	(84)
Net cash provided by (used in) investing activities	751	(116)
Financing activities
Proceeds from borrowings	0	0
Payments on borrowings	(35)	(289)
Proceeds from borrowings from affiliates	50	694
Payments on borrowings from affiliates	(524)	(353)
Capital contributions from affiliates	0	90
Return of capital contributions to affiliates		0
Other intercompany financing activities	(348)	(196)
Cash dividends paid	0	0
Payments of Distributions to Affiliates	0	800
Exercise of employee stock options	0	0
Repurchase of shares	0	0
Payments Related to Tax Withholding for Share-based Compensation	(5)	(4)
Other - net	0	(1)
Net cash provided by (used in) financing activities	(862)	(859)
Effect of currency on cash	0	0
Total increase (decrease) in cash	(8)	(6)
Cash at the beginning of the period	18	12
Cash at the end of the period	10	6
Other subsidiaries [Member]
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	944	1,014
Investing activities
Capital expenditures for property, plant and equipment	(181)	(145)
Sales (purchases) of short-term investments - net	284	(309)
Investments in affiliates	0	(90)
Return of capital contributions from affiliates		0
Loans to affiliates	(3,563)	(3,570)
Repayments of loans from affiliates	3,110	3,035
Other - net	(19)	79
Net cash provided by (used in) investing activities	(369)	(1,000)
Financing activities
Proceeds from borrowings	19	21
Payments on borrowings	(1)	(4)
Proceeds from borrowings from affiliates	100	15
Payments on borrowings from affiliates	(759)	(75)
Capital contributions from affiliates	36	119
Return of capital contributions to affiliates		20
Other intercompany financing activities	(63)	484
Cash dividends paid	0	0
Payments of Distributions to Affiliates	(84)	(707)
Exercise of employee stock options	0	0
Repurchase of shares	0	0
Payments Related to Tax Withholding for Share-based Compensation	(3)	(3)
Other - net	(1)	(3)
Net cash provided by (used in) financing activities	(756)	(173)
Effect of currency on cash	62	7
Total increase (decrease) in cash	(119)	(152)
Cash at the beginning of the period	360	438
Cash at the end of the period	241	286
Eaton Corporation plc [Member]
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	0	573
Investing activities
Capital expenditures for property, plant and equipment	0	0
Sales (purchases) of short-term investments - net	0	0
Investments in affiliates	0	(90)
Return of capital contributions from affiliates		0
Loans to affiliates	0	0
Repayments of loans from affiliates	0	0
Other - net	0	0
Net cash provided by (used in) investing activities	0	(90)
Financing activities
Proceeds from borrowings	0	0
Payments on borrowings	0	0
Proceeds from borrowings from affiliates	2,383	1,288
Payments on borrowings from affiliates	(1,226)	(819)
Capital contributions from affiliates	0	0
Return of capital contributions to affiliates		0
Other intercompany financing activities	0	0
Cash dividends paid	(578)	(537)
Payments of Distributions to Affiliates	0	0
Exercise of employee stock options	21	49
Repurchase of shares	(600)	(465)
Payments Related to Tax Withholding for Share-based Compensation	0	0
Other - net	0	0
Net cash provided by (used in) financing activities	0	(484)
Effect of currency on cash	0	0
Total increase (decrease) in cash	0	(1)
Cash at the beginning of the period	0	1
Cash at the end of the period	0	0
Eaton Corporation [Member]
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	(125)	(12)
Investing activities
Capital expenditures for property, plant and equipment	(48)	(45)
Sales (purchases) of short-term investments - net	0	0
Investments in affiliates	(36)	(29)
Return of capital contributions from affiliates		0
Loans to affiliates	(100)	(17)
Repayments of loans from affiliates	507	291
Other - net	(23)	(26)
Net cash provided by (used in) investing activities	300	174
Financing activities
Proceeds from borrowings	481	811
Payments on borrowings	(450)	(250)
Proceeds from borrowings from affiliates	1,215	1,873
Payments on borrowings from affiliates	(1,994)	(2,366)
Capital contributions from affiliates	0	0
Return of capital contributions to affiliates		0
Other intercompany financing activities	411	(288)
Cash dividends paid	0	0
Payments of Distributions to Affiliates	0	0
Exercise of employee stock options	0	0
Repurchase of shares	0	0
Payments Related to Tax Withholding for Share-based Compensation	(15)	(14)
Other - net	(1)	0
Net cash provided by (used in) financing activities	(353)	(234)
Effect of currency on cash	0	0
Total increase (decrease) in cash	(178)	(72)
Cash at the beginning of the period	183	92
Cash at the end of the period	5	20
Consolidation, Eliminations [Member]
Condensed Consolidating Statements of Cash Flows, Captions [Line Items]
Net cash provided by (used in) operating activities	(84)	(1,507)
Investing activities
Capital expenditures for property, plant and equipment	0	0
Sales (purchases) of short-term investments - net	0	0
Investments in affiliates	36	209
Return of capital contributions from affiliates		(20)
Loans to affiliates	3,748	3,870
Repayments of loans from affiliates	(4,503)	(3,613)
Other - net	0	0
Net cash provided by (used in) investing activities	(719)	446
Financing activities
Proceeds from borrowings	0	0
Payments on borrowings	0	0
Proceeds from borrowings from affiliates	(3,748)	(3,870)
Payments on borrowings from affiliates	4,503	3,613
Capital contributions from affiliates	(36)	(209)
Return of capital contributions to affiliates		20
Other intercompany financing activities	0	0
Cash dividends paid	0	0
Payments of Distributions to Affiliates	84	1,507
Exercise of employee stock options	0	0
Repurchase of shares	0	0
Payments Related to Tax Withholding for Share-based Compensation	0	0
Other - net	0	0
Net cash provided by (used in) financing activities	803	1,061
Effect of currency on cash	0	0
Total increase (decrease) in cash	0	0
Cash at the beginning of the period	0	0
Cash at the end of the period	$ 0	$ 0