Condensed Consolidating Financial Statements (Schedule of Condensed Consolidating Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 26, 2014	Sep. 26, 2014	Dec. 27, 2013	Sep. 27, 2013
Current Assets:
Cash and cash equivalents	$ 899.0	$ 707.8	$ 287.8	$ 275.5
Accounts receivable, net	508.5	545.6
Inventories	369.3	396.6
Deferred income taxes	146.4	165.2
Prepaid expenses and other current assets	141.8	255.8
Intercompany receivable	0	0
Total current assets	2,065.0	2,071.0
Property, plant and equipment, net	945.6	949.2
Goodwill	2,413.7	2,401.9
Intangible assets, net	6,984.9	7,112.2
Investment in subsidiaries	0	0
Intercompany loan receivable	0	0
Other assets	364.4	330.5
Total Assets	12,773.6	12,864.8
Current Liabilities:
Current maturities of long-term debt	22.9	21.2
Accounts payable	122.4	128.7
Accrued payroll and payroll-related costs	44.8	125.1
Accrued royalties	69.0	68.0
Accrued and other current liabilities	505.9	561.8
Intercompany payable	0	0
Total current liabilities	765.0	904.8
Long-term debt	3,942.2	3,951.5
Pension and postretirement benefits	116.2	119.1
Environmental liabilities	62.0	59.9
Deferred income taxes	2,344.1	2,398.6
Other income tax liabilities	120.3	122.6
Intercompany loans payable	0	0
Other liabilities	352.0	350.3
Total liabilities	7,701.8	7,906.8
Shareholders' Equity	5,071.8	4,958.0
Total Liabilities and Shareholders' Equity	12,773.6	12,864.8
Mallinckrodt plc
Current Assets:
Cash and cash equivalents	1.2	0.3	1.1	1.2
Accounts receivable, net	0	0
Inventories	0	0
Deferred income taxes	0	0
Prepaid expenses and other current assets	1.1	0.5
Intercompany receivable	10.9	13.5
Total current assets	13.2	14.3
Property, plant and equipment, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Investment in subsidiaries	703.3	586.8
Intercompany loan receivable	4,396.9	4,385.0
Other assets	0	0
Total Assets	5,113.4	4,986.1
Current Liabilities:
Current maturities of long-term debt	0	0
Accounts payable	10.0	1.2
Accrued payroll and payroll-related costs	0	0.1
Accrued royalties	0	0
Accrued and other current liabilities	1.2	1.1
Intercompany payable	30.4	25.7
Total current liabilities	41.6	28.1
Long-term debt	0	0
Pension and postretirement benefits	0	0
Environmental liabilities	0	0
Deferred income taxes	0	0
Other income tax liabilities	0	0
Intercompany loans payable	0	0
Other liabilities	0	0
Total liabilities	41.6	28.1
Shareholders' Equity	5,071.8	4,958.0
Total Liabilities and Shareholders' Equity	5,113.4	4,986.1
Mallinckrodt International Finance S.A.
Current Assets:
Cash and cash equivalents	139.4	18.5	34.9	56.5
Accounts receivable, net	0	0
Inventories	0	0
Deferred income taxes	0	0
Prepaid expenses and other current assets	0.1	10.8
Intercompany receivable	0	0
Total current assets	139.5	29.3
Property, plant and equipment, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Investment in subsidiaries	10,830.7	10,645.7
Intercompany loan receivable	0	0
Other assets	73.4	76.5
Total Assets	11,043.6	10,751.5
Current Liabilities:
Current maturities of long-term debt	19.9	18.2
Accounts payable	0.4	0.2
Accrued payroll and payroll-related costs	0	0
Accrued royalties	0	0
Accrued and other current liabilities	42.2	50.9
Intercompany payable	0	0
Total current liabilities	62.5	69.3
Long-term debt	3,765.7	3,770.4
Pension and postretirement benefits	0	0
Environmental liabilities	0	0
Deferred income taxes	0	0
Other income tax liabilities	0	0
Intercompany loans payable	2,153.8	1,966.6
Other liabilities	0	0
Total liabilities	5,982.0	5,806.3
Shareholders' Equity	5,061.6	4,945.2
Total Liabilities and Shareholders' Equity	11,043.6	10,751.5
Other Subsidiaries
Current Assets:
Cash and cash equivalents	758.4	689.0	251.8	217.8
Accounts receivable, net	508.5	545.6
Inventories	369.3	396.6
Deferred income taxes	146.4	165.2
Prepaid expenses and other current assets	140.6	244.5
Intercompany receivable	30.4	25.7
Total current assets	1,953.6	2,066.6
Property, plant and equipment, net	945.6	949.2
Goodwill	2,413.7	2,401.9
Intangible assets, net	6,984.9	7,112.2
Investment in subsidiaries	5,061.6	4,945.1
Intercompany loan receivable	2,116.9	1,941.6
Other assets	291.0	254.0
Total Assets	19,767.3	19,670.6
Current Liabilities:
Current maturities of long-term debt	3.0	3.0
Accounts payable	112.0	127.3
Accrued payroll and payroll-related costs	44.8	125.0
Accrued royalties	69.0	68.0
Accrued and other current liabilities	462.5	509.8
Intercompany payable	10.9	13.5
Total current liabilities	702.2	846.6
Long-term debt	176.5	181.1
Pension and postretirement benefits	116.2	119.1
Environmental liabilities	62.0	59.9
Deferred income taxes	2,344.1	2,398.6
Other income tax liabilities	120.3	122.6
Intercompany loans payable	4,360.0	4,360.0
Other liabilities	352.0	350.3
Total liabilities	8,233.3	8,438.2
Shareholders' Equity	11,534.0	11,232.4
Total Liabilities and Shareholders' Equity	19,767.3	19,670.6
Eliminations
Current Assets:
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Inventories	0	0
Deferred income taxes	0	0
Prepaid expenses and other current assets	0	0
Intercompany receivable	(41.3)	(39.2)
Total current assets	(41.3)	(39.2)
Property, plant and equipment, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Investment in subsidiaries	(16,595.6)	(16,177.6)
Intercompany loan receivable	(6,513.8)	(6,326.6)
Other assets	0	0
Total Assets	(23,150.7)	(22,543.4)
Current Liabilities:
Current maturities of long-term debt	0	0
Accounts payable	0	0
Accrued payroll and payroll-related costs	0	0
Accrued royalties	0	0
Accrued and other current liabilities	0	0
Intercompany payable	(41.3)	(39.2)
Total current liabilities	(41.3)	(39.2)
Long-term debt	0	0
Pension and postretirement benefits	0	0
Environmental liabilities	0	0
Deferred income taxes	0	0
Other income tax liabilities	0	0
Intercompany loans payable	(6,513.8)	(6,326.6)
Other liabilities	0	0
Total liabilities	(6,555.1)	(6,365.8)
Shareholders' Equity	(16,595.6)	(16,177.6)
Total Liabilities and Shareholders' Equity	$ (23,150.7)	$ (22,543.4)