Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries - Supplemental Condensed Consolidating Statement of Operations and Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Condensed Financial Statements
Revenue	$ 766.3	$ 729.2	$ 1,491.7	$ 1,411.2
Cost of services, cost of product sales and cost of instant games	278.9	276.2	558.9	532.5
Selling, general and administrative	145.9	144.9	286.6	287.2
Research and development	48.1	51.7	90.5	101.5
Depreciation, amortization and impairments	175.0	193.1	340.1	373.7
Restructuring and other	1.1	4.2	10.3	6.9
Operating (loss) income	117.3	59.1	205.3	109.4
Interest income (expense)	(151.2)	(165.3)	(310.6)	(331.0)
Gain (loss) on extinguishment and modification of debt	0.0	25.2	(29.7)	25.2
Other (expense) income, net	1.2	9.7	18.2	13.6
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	(32.7)	(71.3)	(116.8)	(182.8)
Equity in (loss) income of subsidiaries	0.0	0.0	0.0	0.0
Income tax benefit (expense)	(6.4)	19.6	(23.1)	38.8
Net (loss) income	(39.1)	(51.7)	(139.9)	(144.0)
Other comprehensive income	31.7	(30.2)	67.8	(32.6)
Comprehensive (loss) income	(7.4)	(81.9)	(72.1)	(176.6)
Reportable Legal Entities | SGI (Issuer)
Condensed Financial Statements
Revenue	128.3	126.4	246.3	241.7
Cost of services, cost of product sales and cost of instant games	86.8	86.1	169.7	169.0
Selling, general and administrative	8.5	11.6	18.0	22.8
Research and development	2.4	2.3	3.8	4.6
Depreciation, amortization and impairments	8.0	10.4	15.5	21.1
Restructuring and other	0.3	0.0	0.5	0.0
Operating (loss) income	22.3	16.0	38.8	24.2
Interest income (expense)	(151.1)	(159.9)	(305.7)	(320.5)
Gain (loss) on extinguishment and modification of debt		25.2	(28.6)	25.2
Other (expense) income, net	51.7	52.5	102.4	102.8
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	(77.1)	(66.2)	(193.1)	(168.3)
Equity in (loss) income of subsidiaries	14.6	11.3	31.9	30.2
Income tax benefit (expense)	28.9	0.0	72.3	0.0
Net (loss) income	(33.6)	(54.9)	(88.9)	(138.1)
Other comprehensive income	0.3	3.1	4.3	3.0
Comprehensive (loss) income	(33.3)	(51.8)	(84.6)	(135.1)
Reportable Legal Entities | SGC (Parent and Issuer)
Condensed Financial Statements
Revenue	0.0	0.0	0.0	0.0
Cost of services, cost of product sales and cost of instant games	0.0	0.0	0.0	0.0
Selling, general and administrative	29.2	37.0	58.9	61.0
Research and development	0.7	1.9	1.2	2.8
Depreciation, amortization and impairments	16.9	12.9	37.2	25.8
Restructuring and other	1.5	0.1	5.3	0.1
Operating (loss) income	(48.3)	(51.9)	(102.6)	(89.7)
Interest income (expense)	0.2	(5.3)	(4.3)	(10.5)
Gain (loss) on extinguishment and modification of debt		0.0	(1.1)	0.0
Other (expense) income, net	(18.1)	(24.7)	(38.9)	(50.3)
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	(66.2)	(81.9)	(146.9)	(150.5)
Equity in (loss) income of subsidiaries	18.8	5.3	23.5	(40.7)
Income tax benefit (expense)	8.3	24.9	(16.5)	47.1
Net (loss) income	(39.1)	(51.7)	(139.9)	(144.1)
Other comprehensive income	31.7	(30.1)	67.8	(32.6)
Comprehensive (loss) income	(7.4)	(81.8)	(72.1)	(176.7)
Reportable Legal Entities | Guarantor Subsidiaries
Condensed Financial Statements
Revenue	420.5	354.7	820.3	716.2
Cost of services, cost of product sales and cost of instant games	129.0	92.4	252.7	189.1
Selling, general and administrative	68.9	36.2	117.7	89.7
Research and development	16.9	34.9	51.1	70.8
Depreciation, amortization and impairments	122.8	140.5	234.7	266.7
Restructuring and other	(1.1)	3.2	3.1	4.1
Operating (loss) income	84.0	47.5	161.0	95.8
Interest income (expense)	0.0	0.0	0.0	0.0
Gain (loss) on extinguishment and modification of debt		0.0	0.0	0.0
Other (expense) income, net	(31.0)	(24.1)	(56.5)	(47.2)
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	53.0	23.4	104.5	48.6
Equity in (loss) income of subsidiaries	6.1	26.4	21.5	47.3
Income tax benefit (expense)	(27.4)	0.0	(48.0)	0.0
Net (loss) income	31.7	49.8	78.0	95.9
Other comprehensive income	44.7	(8.1)	66.2	(6.2)
Comprehensive (loss) income	76.4	41.7	144.2	89.7
Reportable Legal Entities | Non-Guarantor Subsidiaries
Condensed Financial Statements
Revenue	284.8	319.4	549.4	583.7
Cost of services, cost of product sales and cost of instant games	135.6	169.0	257.4	304.8
Selling, general and administrative	52.1	60.1	114.5	113.7
Research and development	28.1	12.6	34.4	23.3
Depreciation, amortization and impairments	29.6	29.3	57.4	60.1
Restructuring and other	0.4	0.9	1.4	2.7
Operating (loss) income	39.0	47.5	84.3	79.1
Interest income (expense)	(0.3)	(0.1)	(0.6)	0.0
Gain (loss) on extinguishment and modification of debt		0.0	0.0	0.0
Other (expense) income, net	(1.4)	6.0	11.2	8.3
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	37.3	53.4	94.9	87.4
Equity in (loss) income of subsidiaries	0.0	0.0	0.0	0.0
Income tax benefit (expense)	(16.2)	(5.3)	(30.9)	(8.3)
Net (loss) income	21.1	48.1	64.0	79.1
Other comprehensive income	30.2	(33.5)	59.7	(30.7)
Comprehensive (loss) income	51.3	14.6	123.7	48.4
Eliminating Entries
Condensed Financial Statements
Revenue	(67.3)	(71.3)	(124.3)	(130.4)
Cost of services, cost of product sales and cost of instant games	(72.5)	(71.3)	(120.9)	(130.4)
Selling, general and administrative	(12.8)	0.0	(22.5)	0.0
Research and development	0.0	0.0	0.0	0.0
Depreciation, amortization and impairments	(2.3)	0.0	(4.7)	0.0
Restructuring and other	0.0	0.0	0.0	0.0
Operating (loss) income	20.3	0.0	23.8	0.0
Interest income (expense)	0.0	0.0	0.0	0.0
Gain (loss) on extinguishment and modification of debt		0.0	0.0	0.0
Other (expense) income, net	0.0	0.0	0.0	0.0
Net (loss) income before equity in (loss) income of subsidiaries and income taxes	20.3	0.0	23.8	0.0
Equity in (loss) income of subsidiaries	(39.5)	(43.0)	(76.9)	(36.8)
Income tax benefit (expense)	0.0	0.0	0.0	0.0
Net (loss) income	(19.2)	(43.0)	(53.1)	(36.8)
Other comprehensive income	(75.2)	38.4	(130.2)	33.9
Comprehensive (loss) income	$ (94.4)	$ (4.6)	$ (183.3)	$ (2.9)