CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 02, 2015	Dec. 27, 2013	Jan. 02, 2015	Dec. 27, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 933	$ 428	$ 1,314	$ 855
Cash flow hedges
Change in net unrealized gain (loss) on cash flow hedges	(6)	(2)	(9)	(1)
Less: reclassification for amounts included in net income	2	0	2	0
Net change	(4)	(2)	(7)	(1)
Marketable securities
Change in net unrealized gain (loss) on marketable securities	0	0	0	1
Less: reclassification for amounts included in net income	0	0	0	0
Net change	0	0	0	1
Post-retirement plans
Change in unrealized gain (loss) on post-retirement plans	0	1	0	1
Less: reclassification for amounts included in net income	0	0	0	0
Net change	0	1	0	1
Foreign currency translation adjustments
Foreign currency translation adjustments	(6)	0	(16)	5
Total other comprehensive income (loss), net of tax	(10)	(1)	(23)	6
Comprehensive income	923	427	1,291	861
Less: Comprehensive income attributable to noncontrolling interest	0	0	0	0
Comprehensive income attributable to Seagate Technology plc	$ 923	$ 427	$ 1,291	$ 861