Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries - Supplemental Condensed Consolidating Statement of Operations and Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Condensed Financial Statements
Revenue	$ 845		$ 845		$ 1,682	$ 1,657
Cost of services, cost of product sales and cost of instant products(2)	321		316		628	613
Selling, general and administrative	174		174		360	346
Research and development	46		49		95	103
Depreciation, amortization and impairments	170		173		335	361
Restructuring and other	6		34		13	86
Operating (loss) income	128		99		251	148
Interest expense	(147)		(146)		(301)	(301)
Gain (Loss) on Extinguishment of Debt	(60)		0		(60)	(93)
(Loss) gain on remeasurement of debt	(3)		34		2	33
Other income (expense), net	14		7		20	11
Net (loss) income before equity in income of subsidiaries and income taxes	(68)		(6)		(88)	(202)
Equity in (loss) income of subsidiaries	0		0		0	0
Income tax (expense) benefit	(7)		0		(11)	(6)
Net (loss) income	(75)		(6)		(99)	(208)
Less: Net income attributable to noncontrolling interest	2		0		2	0
Net Income (Loss) Attributable to Parent	(77)	$ (24)	(6)	$ (202)	(101)	(208)
Other comprehensive loss	(51)	$ 51	(83)	$ 52		(31)
Foreign currency translation gain, net of tax	(39)		(88)		16	(37)
Pension and post-retirement gain (loss), net of tax	(1)		1		0	0
Derivative financial instruments unrealized (loss) gain, net of tax	(11)		4		(16)	6
Other Comprehensive Income (Loss), Net of Tax	(51)				0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(126)		(89)		(99)	(239)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	2		0		2	0
Comprehensive loss attributable to SGC	(128)		(89)		(101)	(239)
Reportable Legal Entities | SGI (Issuer)
Condensed Financial Statements
Revenue	147		136		305	266
Cost of services, cost of product sales and cost of instant products(2)	94		86		195	172
Selling, general and administrative	9		9		20	20
Research and development	1		1		2	1
Depreciation, amortization and impairments	13		7		25	15
Restructuring and other	1		(3)		1	(2)
Operating (loss) income	29		36		62	60
Interest expense	(147)		(146)		(301)	(301)
Gain (Loss) on Extinguishment of Debt	(60)				(60)	(93)
(Loss) gain on remeasurement of debt	(3)		34		2	33
Other income (expense), net	131		132		263	269
Net (loss) income before equity in income of subsidiaries and income taxes	(50)		56		(34)	(32)
Equity in (loss) income of subsidiaries	2		13		9	17
Income tax (expense) benefit	14		(26)		9	8
Net (loss) income	(34)				(16)
Less: Net income attributable to noncontrolling interest	0				0
Net Income (Loss) Attributable to Parent	(34)		43		(16)	(7)
Other comprehensive loss			30			12
Other Comprehensive Income (Loss), Net of Tax	(15)				(6)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(49)				(22)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0				0
Comprehensive loss attributable to SGC	(49)		73		(22)	5
Reportable Legal Entities | SGC (Parent)
Condensed Financial Statements
Revenue	0		0		0	0
Cost of services, cost of product sales and cost of instant products(2)	0		0		0	0
Selling, general and administrative	31		44		66	82
Research and development	0		0		0	0
Depreciation, amortization and impairments	12		12		24	21
Restructuring and other	1		30		2	56
Operating (loss) income	(44)		(86)		(92)	(159)
Interest expense	0		0		0	0
Gain (Loss) on Extinguishment of Debt	0				0	0
(Loss) gain on remeasurement of debt	0		0		0	0
Other income (expense), net	16		17		36	33
Net (loss) income before equity in income of subsidiaries and income taxes	(28)		(69)		(56)	(126)
Equity in (loss) income of subsidiaries	(30)		26		(24)	(58)
Income tax (expense) benefit	(19)		37		(21)	(24)
Net (loss) income	(77)				(101)
Less: Net income attributable to noncontrolling interest	0				0
Net Income (Loss) Attributable to Parent	(77)		(6)		(101)	(208)
Other comprehensive loss			(83)			(31)
Other Comprehensive Income (Loss), Net of Tax	(51)				0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(128)				(101)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0				0
Comprehensive loss attributable to SGC	(128)		(89)		(101)	(239)
Reportable Legal Entities | Guarantor Subsidiaries
Condensed Financial Statements
Revenue	358		405		716	792
Cost of services, cost of product sales and cost of instant products(2)	108		132		210	250
Selling, general and administrative	48		51		107	109
Research and development	19		22		42	45
Depreciation, amortization and impairments	104		107		203	233
Restructuring and other	1		2		3	3
Operating (loss) income	78		91		151	152
Interest expense	0		0		0	0
Gain (Loss) on Extinguishment of Debt	0				0	0
(Loss) gain on remeasurement of debt	0		0		0	0
Other income (expense), net	(119)		(119)		(243)	(252)
Net (loss) income before equity in income of subsidiaries and income taxes	(41)		(28)		(92)	(100)
Equity in (loss) income of subsidiaries	12		(17)		23	(7)
Income tax (expense) benefit	9		(4)		22	21
Net (loss) income	(20)				(47)
Less: Net income attributable to noncontrolling interest	0				0
Net Income (Loss) Attributable to Parent	(20)		(49)		(47)	(86)
Other comprehensive loss			(36)			(13)
Other Comprehensive Income (Loss), Net of Tax	(3)				(1)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(23)				(48)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0				0
Comprehensive loss attributable to SGC	(23)		(85)		(48)	(99)
Reportable Legal Entities | Non-Guarantor Subsidiaries
Condensed Financial Statements
Revenue	407		376		792	745
Cost of services, cost of product sales and cost of instant products(2)	176		159		328	313
Selling, general and administrative	94		83		188	162
Research and development	26		26		51	57
Depreciation, amortization and impairments	45		50		92	98
Restructuring and other	3		5		7	29
Operating (loss) income	63		53		126	86
Interest expense	0		0		0	0
Gain (Loss) on Extinguishment of Debt	0				0	0
(Loss) gain on remeasurement of debt	0		0		0	0
Other income (expense), net	(14)		(23)		(36)	(39)
Net (loss) income before equity in income of subsidiaries and income taxes	49		30		90	47
Equity in (loss) income of subsidiaries	0		0		0	0
Income tax (expense) benefit	(11)		(7)		(21)	(11)
Net (loss) income	38				69
Less: Net income attributable to noncontrolling interest	2				2
Net Income (Loss) Attributable to Parent	36		23		67	36
Other comprehensive loss			(119)			(46)
Other Comprehensive Income (Loss), Net of Tax	(66)				5
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(28)				74
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	2				2
Comprehensive loss attributable to SGC	(30)		(96)		72	(10)
Eliminating Entries
Condensed Financial Statements
Revenue	(67)		(72)		(131)	(146)
Cost of services, cost of product sales and cost of instant products(2)	(57)		(61)		(105)	(122)
Selling, general and administrative	(8)		(13)		(21)	(27)
Research and development	0		0		0	0
Depreciation, amortization and impairments	(4)		(3)		(9)	(6)
Restructuring and other	0		0		0	0
Operating (loss) income	2		5		4	9
Interest expense	0		0		0	0
Gain (Loss) on Extinguishment of Debt	0				0	0
(Loss) gain on remeasurement of debt	0		0		0	0
Other income (expense), net	0		0		0	0
Net (loss) income before equity in income of subsidiaries and income taxes	2		5		4	9
Equity in (loss) income of subsidiaries	16		(22)		(8)	48
Income tax (expense) benefit	0		0		0	0
Net (loss) income	18				(4)
Less: Net income attributable to noncontrolling interest	0				0
Net Income (Loss) Attributable to Parent	18		(17)		(4)	57
Other comprehensive loss			125			47
Other Comprehensive Income (Loss), Net of Tax	84				2
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	102				(2)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0				0
Comprehensive loss attributable to SGC	$ 102		$ 108		$ (2)	$ 104