Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($)	12 Months Ended
	Sep. 30, 2016	Sep. 25, 2015	Mar. 25, 2016	Mar. 10, 2016	Aug. 07, 2015	Jun. 22, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of days in fiscal year	371 days	364 days
Cash per share each JCI share will be converted to upon effect of the merger			$ 34.88
Amount to be received by JCI Shareholders			$ 3,864,000,000
Amount of shares each tyco share will be consolidated into upon effect of JCI merger			0.955
bank facility			$ 4,000,000,000
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,500,000,000.0	$ 1,000,000,000	$ 1,500,000,000	$ 1,000,000,000