Guarantor Financial Statements (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 25, 2016	Mar. 27, 2015	Mar. 25, 2016	Mar. 27, 2015	Sep. 25, 2015	Sep. 26, 2014	Jun. 27, 2014
Condensed Financial Information Disclosure [Abstract]
Net revenue	$ 2,331	$ 2,430	$ 4,707	$ 4,908
Net income	145	165	221	326
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	2	0	3	0
Current Assets:
Cash and cash equivalents	345		345		$ 1,401	$ 892	$ 432
Accounts receivable, net	1,722		1,722		1,732
Inventories	670		670		624
Prepaid expenses and other current assets	864		864		754
Deferred income taxes	62		62		62
Assets held for sale	0		0		102
Total Current Assets	3,663		3,663		4,675
Property, plant and equipment, net	1,189		1,189		1,177
Goodwill	4,460		4,460		4,234	4,119
Intangible assets, net	1,025		1,025		863
Other assets	1,274		1,274		1,372
Total Assets	11,611		11,611		12,321
Current Liabilities:
Loans payable and current maturities of long-term debt	400		400		987
Accounts payable	797		797		774
Accrued and other current liabilities	1,643		1,643		1,661
Deferred revenue	393		393		380
Liabilities held for sale	0		0		50
Total Current Liabilities	3,233		3,233		3,852
Long-term debt	2,159		2,159		2,159
Deferred revenue	285		285		303
Other liabilities	1,756		1,756		1,931
Total Liabilities	7,433		7,433		8,245
Tyco Shareholders' Equity:
Common shares	4		4		4
Common shares held in treasury	(15)		(15)		(3)
Other shareholders' equity	4,153		4,153		4,037
Total Tyco Shareholders' Equity	4,142		4,142		4,041
Nonredeemable noncontrolling interest	36		36		35
Total Equity	4,178	4,230	4,178	4,230	4,076	4,670
Total Liabilities and Equity	11,611		11,611		12,321
Foreign currency translation	44	(176)	1	(374)
Defined benefit and post retirement plans	3	4	8	9
Other comprehensive loss, net of tax	49	(172)	12	(365)
Comprehensive income (loss)	194	(7)	233	(39)
Less: comprehensive loss attributable to noncontrolling interests	(1)	(2)	(1)	(3)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	195	(5)	234	(36)
Cost of product sales	968	999	1,930	2,021
Cost of services	506	550	1,042	1,097
Selling, general and administrative expenses	602	648	1,175	1,300
Restructuring and asset impairment charges, net	4	12	16	70
Operating Income (Loss)	225	221	518	420
Interest income	4	4	8	7
Interest Expense	(22)	(25)	(46)	(49)
Other (expense) income, net	0	(1)	(165)	3
Equity in net income of subsidiaries	0	0	0	0
Intercompany Interest and Fees	0	0	0	0
Income (Loss) from Continuing Operations before Income and Minority Interest	207	199	315	381
Income tax expense	(63)	(18)	(99)	(37)
Income from continuing operations	144	181	216	344
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	1	(16)	5	(18)
Noncontrolling interest in subsidiaries net income	(1)	(2)	(1)	(3)
Net Income (Loss) Attributable to Parent	146	167	222	329
Separation Transaction and Merger Costs	26	0	26	0
Tyco International plc
Condensed Financial Information Disclosure [Abstract]
Net income	146	167	222	329
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	2		3
Current Assets:
Accounts receivable, net					0
Intercompany receivables	15		15		15
Prepaid expenses and other current assets	1		1		0
Total Current Assets	16		16		15
Investment in subsidiaries	11,086		11,086		10,885
Intercompany loans receivable	0		0		0
Other assets	1		1		1
Total Assets	11,103		11,103		10,901
Current Liabilities:
Accounts payable	2		2		1
Accrued and other current liabilities	89		89		88
Intercompany payables	3,704		3,704		3,616
Total Current Liabilities	3,795		3,795		3,705
Intercompany loans payable	3,166		3,166		3,155
Other liabilities	0		0		0
Total Liabilities	6,961		6,961		6,860
Tyco Shareholders' Equity:
Common shares	4		4		4
Common shares held in treasury	(15)		(15)
Other shareholders' equity	4,153		4,153		4,037
Total Tyco Shareholders' Equity	4,142		4,142		4,041
Total Equity	4,142		4,142		4,041
Total Liabilities and Equity	11,103		11,103		10,901
Foreign currency translation	44	(176)	1	(374)
Defined benefit and post retirement plans	3	4	8	9
Other comprehensive loss, net of tax	49	(172)	12	(365)
Comprehensive income (loss)	195	(5)	234	(36)
Less: comprehensive loss attributable to noncontrolling interests		0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	195	(5)	234	(36)
Selling, general and administrative expenses	2	2	4	5
Operating Income (Loss)	(2)	(2)	(4)	(5)
Interest income	0	0	0	0
Interest Expense	0	0	0	0
Other (expense) income, net	0	0	0	0
Equity in net income of subsidiaries	145	152	163	295
Intercompany Interest and Fees	5	17	65	39
Income (Loss) from Continuing Operations before Income and Minority Interest	148	167	224	329
Income tax expense	(2)	0	(2)	0
Income from continuing operations	146	167	222	329
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	0	0	0
Net Income (Loss) Attributable to Parent	146	167	222	329
Tyco Fire & Security Finance SCA [Member]
Condensed Financial Information Disclosure [Abstract]
Net income	144	158	160	291
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	0		0
Current Assets:
Accounts receivable, net					0
Intercompany receivables	0		0		0
Prepaid expenses and other current assets	0		0		0
Total Current Assets	0		0		0
Investment in subsidiaries	11,343		11,343		11,148
Intercompany loans receivable	0		0		0
Other assets	0		0		0
Total Assets	11,343		11,343		11,148
Current Liabilities:
Accounts payable	0		0		0
Accrued and other current liabilities	0		0		0
Intercompany payables	0		0		0
Total Current Liabilities	0		0		0
Intercompany loans payable	0		0		0
Other liabilities	0		0		0
Total Liabilities	0		0		0
Tyco Shareholders' Equity:
Common shares	0		0		0
Other shareholders' equity	11,343		11,343		11,148
Total Tyco Shareholders' Equity	11,343		11,343		11,148
Total Equity	11,343		11,343		11,148
Total Liabilities and Equity	11,343		11,343		11,148
Foreign currency translation	0	0	0	0
Defined benefit and post retirement plans	0	0	0	0
Other comprehensive loss, net of tax	0	0	0	0
Comprehensive income (loss)	144	158	160	291
Less: comprehensive loss attributable to noncontrolling interests		0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	144	158	160	291
Selling, general and administrative expenses	0	0	0	0
Operating Income (Loss)	0	0	0	0
Interest income	0	0	0	0
Interest Expense	0	0	0	0
Other (expense) income, net	0	0	0	0
Equity in net income of subsidiaries	144	158	160	291
Intercompany Interest and Fees	0	0	0	0
Income (Loss) from Continuing Operations before Income and Minority Interest	144	158	160	291
Income tax expense	0	0	0	0
Income from continuing operations	144	158	160	291
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	0	0	0
Net Income (Loss) Attributable to Parent	144	158	160	291
Tyco International Finance S.A.
Condensed Financial Information Disclosure [Abstract]
Net income	144	158	160	291
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	0		0
Current Assets:
Intercompany receivables	496		496		332
Prepaid expenses and other current assets	58		58		63
Total Current Assets	554		554		395
Investment in subsidiaries	16,373		16,373		16,001
Intercompany loans receivable	2,937		2,937		2,942
Other assets	50		50		44
Total Assets	19,914		19,914		19,382
Current Liabilities:
Loans payable and current maturities of long-term debt	400		400		967
Accrued and other current liabilities	96		96		61
Intercompany payables	3,931		3,931		2,892
Total Current Liabilities	4,427		4,427		3,920
Long-term debt	2,158		2,158		2,158
Intercompany loans payable	1,934		1,934		1,911
Other liabilities	52		52		245
Total Liabilities	8,571		8,571		8,234
Tyco Shareholders' Equity:
Other shareholders' equity	11,343		11,343		11,148
Total Tyco Shareholders' Equity	11,343		11,343		11,148
Total Equity	11,343		11,343		11,148
Total Liabilities and Equity	19,914		19,914		19,382
Foreign currency translation	(13)	16	1	15
Defined benefit and post retirement plans		0
Other comprehensive loss, net of tax	(13)	16	1	15
Comprehensive income (loss)	131	174	161	306
Less: comprehensive loss attributable to noncontrolling interests		0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	131	174	161	306
Selling, general and administrative expenses	1	0	1	1
Operating Income (Loss)	(11)	0	(11)	(1)
Interest Expense	(22)	(24)	(45)	(48)
Other (expense) income, net	(1)	(2)	(166)	2
Equity in net income of subsidiaries	156	160	335	287
Intercompany Interest and Fees	22	24	47	51
Income (Loss) from Continuing Operations before Income and Minority Interest	144	158	160	291
Income tax expense	0	0	0	0
Income from continuing operations	144	158	160	291
Net Income (Loss) Attributable to Parent	144	158	160	291
Separation Transaction and Merger Costs	10		10
Other Subsidiaries
Condensed Financial Information Disclosure [Abstract]
Net revenue	2,331	2,430	4,707	4,908
Net income	156	152	337	288
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	2		3
Current Assets:
Cash and cash equivalents	345		345		1,401	$ 892	432
Accounts receivable, net	1,722		1,722		1,732
Inventories	670		670		624
Intercompany receivables	7,629		7,629		6,508
Prepaid expenses and other current assets	805		805		691
Deferred income taxes	62		62		62
Assets held for sale					102
Total Current Assets	11,233		11,233		11,120
Property, plant and equipment, net	1,189		1,189		1,177
Goodwill	4,460		4,460		4,234
Intangible assets, net	1,025		1,025		863
Intercompany loans receivable	5,100		5,100		5,066
Other assets	1,223		1,223		1,327
Total Assets	24,230		24,230		23,787
Current Liabilities:
Loans payable and current maturities of long-term debt	0		0		20
Accounts payable	795		795		773
Accrued and other current liabilities	1,458		1,458		1,512
Deferred revenue	393		393		380
Intercompany payables	505		505		347
Liabilities held for sale					50
Total Current Liabilities	3,151		3,151		3,082
Long-term debt	1		1		1
Intercompany loans payable	2,937		2,937		2,942
Deferred revenue	285		285		303
Other liabilities	1,704		1,704		1,686
Total Liabilities	8,078		8,078		8,014
Tyco Shareholders' Equity:
Common shares held in treasury	0		0
Other shareholders' equity	16,116		16,116		15,738
Total Tyco Shareholders' Equity	16,116		16,116		15,738
Nonredeemable noncontrolling interest	36		36		35
Total Equity	16,152		16,152		15,773
Total Liabilities and Equity	24,230		24,230		23,787
Foreign currency translation	57	(192)	0	(389)
Defined benefit and post retirement plans	3	4	8	9
Other comprehensive loss, net of tax	62	(188)	11	(380)
Comprehensive income (loss)	218	(36)	348	(92)
Less: comprehensive loss attributable to noncontrolling interests	(1)	(2)	(1)	(3)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	219	(34)	349	(89)
Cost of product sales	968	999	1,930	2,021
Cost of services	506	550	1,042	1,097
Selling, general and administrative expenses	599	646	1,170	1,294
Restructuring and asset impairment charges, net	4	12	16	70
Operating Income (Loss)	238	223	533	426
Interest income	4	4	8	7
Interest Expense	0	(1)	(1)	(1)
Other (expense) income, net	1	1	1	1
Intercompany Interest and Fees	(27)	(41)	(112)	(90)
Income (Loss) from Continuing Operations before Income and Minority Interest	216	186	429	343
Income tax expense	(61)	(18)	(97)	(37)
Income from continuing operations	155	168	332	306
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	1	(16)	5	(18)
Noncontrolling interest in subsidiaries net income	(1)	(2)	(1)	(3)
Net Income (Loss) Attributable to Parent	157	154	338	291
Separation Transaction and Merger Costs	16		16
Consolidating Adjustments
Condensed Financial Information Disclosure [Abstract]
Net income	(445)	(470)	(658)	(873)
Condensed Financial Statements, Captions
Unrealized gain on marketable securities and derivative instruments, net of tax	(2)		(3)
Current Assets:
Cash and cash equivalents							$ 0
Intercompany receivables	(8,140)		(8,140)		(6,855)
Total Current Assets	(8,140)		(8,140)		(6,855)
Investment in subsidiaries	(38,802)		(38,802)		(38,034)
Intercompany loans receivable	(8,037)		(8,037)		(8,008)
Total Assets	(54,979)		(54,979)		(52,897)
Current Liabilities:
Intercompany payables	(8,140)		(8,140)		(6,855)
Total Current Liabilities	(8,140)		(8,140)		(6,855)
Intercompany loans payable	(8,037)		(8,037)		(8,008)
Total Liabilities	(16,177)		(16,177)		(14,863)
Tyco Shareholders' Equity:
Other shareholders' equity	(38,802)		(38,802)		(38,034)
Total Tyco Shareholders' Equity	(38,802)		(38,802)		(38,034)
Total Equity	(38,802)		(38,802)		(38,034)
Total Liabilities and Equity	(54,979)		(54,979)		$ (52,897)
Foreign currency translation	(44)	176	(1)	374
Defined benefit and post retirement plans	(3)	(4)	(8)	(9)
Other comprehensive loss, net of tax	(49)	172	(12)	365
Comprehensive income (loss)	(494)	(298)	(670)	(508)
Less: comprehensive loss attributable to noncontrolling interests		0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(494)	(298)	(670)	(508)
Equity in net income of subsidiaries	(445)	(470)	(658)	(873)
Intercompany Interest and Fees	0	0	0	0
Income (Loss) from Continuing Operations before Income and Minority Interest	(445)	(470)	(658)	(873)
Income from continuing operations	(445)	(470)	(658)	(873)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	0	0	0	0
Net Income (Loss) Attributable to Parent	$ (445)	$ (470)	$ (658)	$ (873)