Guarantor Financial Information (Consolidating Statements of Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
Product sales	$ 3,591.8	$ 2,322.1	$ 7,004.1	$ 3,949.4
Royalties and other revenues	154.0	107.0	314.0	189.0
Total revenues	3,745.8	2,429.1	7,318.1	4,138.4
Costs and expenses:
Cost of sales	1,108.9	778.1	2,435.9	1,026.7
Research and development	542.4	294.8	921.7	511.9
Selling, general and administrative	899.1	675.3	1,788.0	1,150.2
Amortization of acquired intangible assets	434.1	213.0	798.1	347.6
Integration and acquisition costs	343.7	363.0	459.7	454.1
Reorganization costs	13.6	11.0	19.1	14.3
Gain/(loss) on sale of product rights	(4.8)	2.3	0.7	6.5
Total operating expenses	3,346.6	2,332.9	6,421.8	3,498.3
Operating income from continuing operations	399.2	96.2	896.3	640.1
Interest (expense)/income, net	(140.2)	(85.6)	(279.4)	(129.3)
Other income/(expense), net	2.5	6.0	7.0	(2.5)
Total other expense, net	(137.7)	(79.6)	(272.4)	(131.8)
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	261.5	16.6	623.9	508.3
Income taxes	(24.3)	70.9	(31.1)	(11.2)
Equity in income/(losses) of equity method investees, net of taxes	4.3	(0.9)	3.5	(1.0)
Income from continuing operations, net of taxes	241.5	86.6	596.3	496.1
(Loss)/gain from discontinued operations, net of taxes	(1.2)	(248.7)	19.0	(239.2)
Net income/(loss)	240.3	(162.1)	615.3	256.9
Comprehensive income/(loss)	1,667.5	(388.5)	2,313.0	54.9
Eliminations
Revenues:
Product sales	0.0	0.0	0.0	0.0
Royalties and other revenues	0.0	0.0	0.0	0.0
Total revenues	0.0	0.0	0.0	0.0
Costs and expenses:
Cost of sales	0.0	0.0	0.0	0.0
Research and development	0.0	0.0	0.0	0.0
Selling, general and administrative	0.0	0.0	0.0	0.0
Amortization of acquired intangible assets	0.0	0.0	0.0	0.0
Integration and acquisition costs	0.0	0.0	0.0	0.0
Reorganization costs	0.0	0.0	0.0	0.0
Gain/(loss) on sale of product rights	0.0	0.0	0.0	0.0
Total operating expenses	0.0	0.0	0.0	0.0
Operating income from continuing operations	0.0	0.0	0.0	0.0
Interest (expense)/income, net	0.0	0.0	0.0	0.0
Other income/(expense), net	0.0	0.0	0.0	0.0
Total other expense, net	0.0	0.0	0.0	0.0
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	0.0	0.0	0.0	0.0
Income taxes	0.0	0.0	0.0	0.0
Equity in income/(losses) of equity method investees, net of taxes	(525.7)	253.7	(816.7)	(203.5)
Income from continuing operations, net of taxes	(525.7)	253.7	(816.7)	(203.5)
(Loss)/gain from discontinued operations, net of taxes	0.0	0.0	0.0	0.0
Net income/(loss)	(525.7)	253.7	(816.7)	(203.5)
Comprehensive income/(loss)	(3,328.0)	665.5	(4,134.8)	184.8
Shire plc (Parent Guarantor)
Revenues:
Product sales	0.0	0.0	0.0	0.0
Royalties and other revenues	0.0	0.0	0.0	0.0
Total revenues	0.0	0.0	0.0	0.0
Costs and expenses:
Cost of sales	0.0	0.0	0.0	0.0
Research and development	0.0	0.0	0.0	0.0
Selling, general and administrative	8.7	18.8	18.1	35.8
Amortization of acquired intangible assets	0.0	0.0	0.0	0.0
Integration and acquisition costs	160.1		164.7	0.0
Reorganization costs	0.0	0.0	0.0	0.0
Gain/(loss) on sale of product rights	0.0	0.0	0.0	0.0
Total operating expenses	168.8	18.8	182.8	35.8
Operating income from continuing operations	(168.8)	(18.8)	(182.8)	(35.8)
Interest (expense)/income, net	(30.8)	(22.6)	(61.1)	(44.5)
Other income/(expense), net	1.8	1.2	1.8	0.9
Total other expense, net	(29.0)	(21.4)	(59.3)	(43.6)
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	(197.8)	(40.2)	(242.1)	(79.4)
Income taxes	(0.7)	0.9	0.8	1.9
Equity in income/(losses) of equity method investees, net of taxes	438.8	(122.8)	856.6	334.4
Income from continuing operations, net of taxes	240.3	(162.1)	615.3	256.9
(Loss)/gain from discontinued operations, net of taxes	0.0	0.0	0.0	0.0
Net income/(loss)	240.3	(162.1)	615.3	256.9
Comprehensive income/(loss)	1,667.5	(388.5)	2,313.0	54.9
SAIIDAC (SAIIDAC Notes Subsidiary Issuer)
Revenues:
Product sales	0.0	0.0	0.0	0.0
Royalties and other revenues	0.0	0.0	0.0	0.0
Total revenues	0.0	0.0	0.0	0.0
Costs and expenses:
Cost of sales	0.0	0.0	0.0	0.0
Research and development	0.0	0.0	0.0	0.0
Selling, general and administrative	0.0	0.0	0.0	0.0
Amortization of acquired intangible assets	0.0	0.0	0.0	0.0
Integration and acquisition costs	0.0	0.0	0.0	0.0
Reorganization costs	0.0	0.0	0.0	0.0
Gain/(loss) on sale of product rights	0.0	0.0	0.0	0.0
Total operating expenses	0.0	0.0	0.0	0.0
Operating income from continuing operations	0.0	0.0	0.0	0.0
Interest (expense)/income, net	6.1	1.6	11.5	(20.2)
Other income/(expense), net	0.0	0.0	0.0	0.0
Total other expense, net	6.1	1.6	11.5	(20.2)
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	6.1	1.6	11.5	(20.2)
Income taxes	(2.9)	(0.4)	(4.2)	5.1
Equity in income/(losses) of equity method investees, net of taxes	0.0	0.0	0.0	0.0
Income from continuing operations, net of taxes	3.2	1.2	7.3	(15.1)
(Loss)/gain from discontinued operations, net of taxes	0.0	0.0	0.0	0.0
Net income/(loss)	3.2	1.2	7.3	(15.1)
Comprehensive income/(loss)	3.2	1.2	7.3	(15.1)
Baxalta Inc. (Baxalta Notes Subsidiary Issuer and SAIIDAC Notes Subsidiary Guarantor)
Revenues:
Product sales	0.0	0.0	0.0	0.0
Royalties and other revenues	0.0	0.0	0.0	0.0
Total revenues	0.0	0.0	0.0	0.0
Costs and expenses:
Cost of sales	0.2	0.0	1.4	0.0
Research and development	0.0	0.0	0.0	0.0
Selling, general and administrative	4.2	6.9	9.9	6.9
Amortization of acquired intangible assets	0.0	0.0	0.0	0.0
Integration and acquisition costs	17.5	211.8	43.1	211.8
Reorganization costs	0.0	0.0	0.0	0.0
Gain/(loss) on sale of product rights	0.0	0.0	0.0	0.0
Total operating expenses	21.9	218.7	54.4	218.7
Operating income from continuing operations	(21.9)	(218.7)	(54.4)	(218.7)
Interest (expense)/income, net	(21.5)	(6.3)	(42.9)	(6.3)
Other income/(expense), net	(0.6)	7.7	(0.1)	7.7
Total other expense, net	(22.1)	1.4	(43.0)	1.4
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	(44.0)	(217.3)	(97.4)	(217.3)
Income taxes	(16.2)	58.8	(36.1)	58.8
Equity in income/(losses) of equity method investees, net of taxes	86.9	(130.9)	(39.9)	(130.9)
Income from continuing operations, net of taxes	26.7	(289.4)	(173.4)	(289.4)
(Loss)/gain from discontinued operations, net of taxes	0.0	0.0	0.0	0.0
Net income/(loss)	26.7	(289.4)	(173.4)	(289.4)
Comprehensive income/(loss)	1,401.8	(475.6)	1,450.5	(475.6)
Non-Guarantor Non-Issuer Subsidiaries
Revenues:
Product sales	3,591.8	2,322.1	7,004.1	3,949.4
Royalties and other revenues	154.0	107.0	314.0	189.0
Total revenues	3,745.8	2,429.1	7,318.1	4,138.4
Costs and expenses:
Cost of sales	1,108.7	778.1	2,434.5	1,026.7
Research and development	542.4	294.8	921.7	511.9
Selling, general and administrative	886.2	649.6	1,760.0	1,107.5
Amortization of acquired intangible assets	434.1	213.0	798.1	347.6
Integration and acquisition costs	166.1	151.2	251.9	242.3
Reorganization costs	13.6	11.0	19.1	14.3
Gain/(loss) on sale of product rights	(4.8)	2.3	0.7	6.5
Total operating expenses	3,155.9	2,095.4	6,184.6	3,243.8
Operating income from continuing operations	589.9	333.7	1,133.5	894.6
Interest (expense)/income, net	(94.0)	(58.3)	(186.9)	(58.3)
Other income/(expense), net	1.3	(2.9)	5.3	(11.1)
Total other expense, net	(92.7)	(61.2)	(181.6)	(69.4)
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	497.2	272.5	951.9	825.2
Income taxes	(4.5)	11.6	8.4	(77.0)
Equity in income/(losses) of equity method investees, net of taxes	4.3	(0.9)	3.5	(1.0)
Income from continuing operations, net of taxes	497.0	283.2	963.8	747.2
(Loss)/gain from discontinued operations, net of taxes	(1.2)	(248.7)	19.0	(239.2)
Net income/(loss)	495.8	34.5	982.8	508.0
Comprehensive income/(loss)	1,923.0	(191.1)	2,677.0	305.9
Non-Guarantor Subsidiaries of Baxalta Notes
Revenues:
Product sales	3,591.8	2,322.1	7,004.1	3,949.4
Royalties and other revenues	154.0	107.0	314.0	189.0
Total revenues	3,745.8	2,429.1	7,318.1	4,138.4
Costs and expenses:
Cost of sales	1,108.7	778.1	2,434.5	1,026.7
Research and development	542.4	294.8	921.7	511.9
Selling, general and administrative	886.2	649.6	1,760.0	1,107.5
Amortization of acquired intangible assets	434.1	213.0	798.1	347.6
Integration and acquisition costs	166.1	151.2	251.9	242.3
Reorganization costs	13.6	11.0	19.1	14.3
Gain/(loss) on sale of product rights	(4.8)	2.3	0.7	6.5
Total operating expenses	3,155.9	2,095.4	6,184.6	3,243.8
Operating income from continuing operations	589.9	333.7	1,133.5	894.6
Interest (expense)/income, net	(87.9)	(56.7)	(175.4)	(78.5)
Other income/(expense), net	1.3	(2.9)	5.3	(11.1)
Total other expense, net	(86.6)	(59.6)	(170.1)	(89.6)
Income from continuing operations before income taxes and equity in earnings/(losses) of equity method investees	503.3	274.1	963.4	805.0
Income taxes	(7.4)	11.2	4.2	(71.9)
Equity in income/(losses) of equity method investees, net of taxes	4.3	(0.9)	3.5	(1.0)
Income from continuing operations, net of taxes	500.2	284.4	971.1	732.1
(Loss)/gain from discontinued operations, net of taxes	(1.2)	(248.7)	19.0	(239.2)
Net income/(loss)	499.0	35.7	990.1	492.9
Comprehensive income/(loss)	$ 1,926.2	$ (189.9)	$ 2,684.3	$ 290.8