Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries - Supplemental Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 198.2	$ 115.1
Restricted cash	26.0	24.7
Accounts receivable, net	479.3	495.0
Notes receivable, net	123.3	125.4
Inventories	252.7	242.3
Prepaid expenses, deposits and other current assets	117.6	114.1
Property and equipment, net	574.8	612.2
Investment in subsidiaries	0.0	0.0
Goodwill	2,930.7	2,888.4
Intangible assets, net	1,710.3	1,768.3
Intercompany balances	0.0	0.0
Software, net	378.7	409.1
Other assets	274.4	292.8
Total assets	7,066.0	7,087.4
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	39.5	49.3
Other current liabilities	647.4	643.1
Long-term debt, excluding current portion	8,062.7	8,024.9
Other long-term liabilities	314.5	305.8
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	(1,998.1)	(1,935.7)
Total liabilities and stockholders' (deficit) equity	7,066.0	7,087.4
Non-current restricted cash	16.6	17.1
Reportable Legal Entities | SGI (Issuer)
Assets
Cash and cash equivalents	2.8	1.7
Restricted cash	0.0	0.0
Accounts receivable, net	63.7	61.4
Notes receivable, net	0.0	0.0
Inventories	40.6	40.3
Prepaid expenses, deposits and other current assets	23.8	15.7
Property and equipment, net	90.3	98.4
Investment in subsidiaries	958.9	926.7
Goodwill	188.3	188.3
Intangible assets, net	36.5	37.5
Intercompany balances	5,478.8	5,415.1
Software, net	20.0	21.4
Other assets	305.0	236.5
Total assets	7,208.7	7,043.0
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	32.9	43.0
Other current liabilities	170.2	158.7
Long-term debt, excluding current portion	8,056.9	7,767.3
Other long-term liabilities	9.1	12.4
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	(1,060.4)	(938.4)
Total liabilities and stockholders' (deficit) equity	7,208.7	7,043.0
Reportable Legal Entities | SGC (Parent and Issuer)
Assets
Cash and cash equivalents	142.7	32.7
Restricted cash	0.0	0.0
Accounts receivable, net	0.1	0.0
Notes receivable, net	0.0	0.0
Inventories	0.0	0.0
Prepaid expenses, deposits and other current assets	7.4	11.6
Property and equipment, net	14.8	5.6
Investment in subsidiaries	3,099.8	3,000.7
Goodwill	0.0	0.0
Intangible assets, net	183.2	185.8
Intercompany balances	0.0	0.0
Software, net	77.6	74.7
Other assets	233.9	233.6
Total assets	3,759.5	3,544.7
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	105.9	100.5
Long-term debt, excluding current portion	0.0	248.7
Other long-term liabilities	171.0	159.0
Intercompany balances	5,480.7	4,972.2
Stockholders' (deficit) equity	(1,998.1)	(1,935.7)
Total liabilities and stockholders' (deficit) equity	3,759.5	3,544.7
Reportable Legal Entities | Guarantor Subsidiaries
Assets
Cash and cash equivalents	0.0	0.0
Restricted cash	25.9	24.6
Accounts receivable, net	182.1	199.2
Notes receivable, net	99.2	94.4
Inventories	93.0	83.1
Prepaid expenses, deposits and other current assets	41.9	45.6
Property and equipment, net	330.2	369.3
Investment in subsidiaries	967.1	944.0
Goodwill	1,932.4	1,931.6
Intangible assets, net	1,278.0	1,343.0
Intercompany balances	0.0	0.0
Software, net	233.0	264.6
Other assets	57.3	50.8
Total assets	5,240.1	5,350.2
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	212.7	216.3
Long-term debt, excluding current portion	0.0	0.0
Other long-term liabilities	517.2	468.8
Intercompany balances	313.1	559.5
Stockholders' (deficit) equity	4,197.1	4,105.6
Total liabilities and stockholders' (deficit) equity	5,240.1	5,350.2
Non-current restricted cash	15.9	16.4
Reportable Legal Entities | Non-Guarantor Subsidiaries
Assets
Cash and cash equivalents	53.4	81.8
Restricted cash	0.1	0.1
Accounts receivable, net	233.4	234.4
Notes receivable, net	24.1	31.0
Inventories	147.2	138.1
Prepaid expenses, deposits and other current assets	44.5	41.2
Property and equipment, net	161.5	154.9
Investment in subsidiaries	0.0	0.0
Goodwill	810.0	768.5
Intangible assets, net	212.6	202.0
Intercompany balances	315.0	116.6
Software, net	48.1	48.4
Other assets	150.4	173.5
Total assets	2,200.3	1,990.5
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	6.6	6.3
Other current liabilities	161.0	168.7
Long-term debt, excluding current portion	5.8	8.9
Other long-term liabilities	87.7	67.2
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	1,939.2	1,739.4
Total liabilities and stockholders' (deficit) equity	2,200.3	1,990.5
Non-current restricted cash	0.7	0.7
Eliminating Entries
Assets
Cash and cash equivalents	(0.7)	(1.1)
Restricted cash	0.0	0.0
Accounts receivable, net	0.0	0.0
Notes receivable, net	0.0	0.0
Inventories	(28.1)	(19.2)
Prepaid expenses, deposits and other current assets	0.0	0.0
Property and equipment, net	(22.0)	(16.0)
Investment in subsidiaries	(5,025.8)	(4,871.4)
Goodwill	0.0	0.0
Intangible assets, net	0.0	0.0
Intercompany balances	(5,793.8)	(5,531.7)
Software, net	0.0	0.0
Other assets	(472.2)	(401.6)
Total assets	(11,342.6)	(10,841.0)
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	(2.4)	(1.1)
Long-term debt, excluding current portion	0.0	0.0
Other long-term liabilities	(470.5)	(401.6)
Intercompany balances	(5,793.8)	(5,531.7)
Stockholders' (deficit) equity	(5,075.9)	(4,906.6)
Total liabilities and stockholders' (deficit) equity	$ (11,342.6)	$ (10,841.0)