Financial Information for Guarantor Subsidiaries and Non-Guarantor Subsidiaries - Supplemental Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 131.9	$ 115.1
Restricted cash	27.1	24.7
Accounts receivable, net	463.5	495.0
Notes receivable, net	131.0	125.4
Inventories	253.5	242.3
Prepaid expenses, deposits and other current assets	113.2	114.1
Property and equipment, net	584.7	612.2
Investment in subsidiaries	0.0	0.0
Goodwill	2,906.1	2,888.4
Intangible assets, net	1,761.9	1,768.3
Intercompany balances	0.0	0.0
Software, net	395.5	409.1
Other assets	304.8	292.8
Total assets	7,073.2	7,087.4
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	39.3	49.3
Other current liabilities	646.2	643.1
Long-term debt, excluding current portion	8,068.4	8,024.9
Other long-term liabilities	314.5	305.8
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	(1,995.2)	(1,935.7)
Total liabilities and stockholders' (deficit) equity	7,073.2	7,087.4
Non-current restricted cash	16.8	17.1
Eliminating Entries
Assets
Cash and cash equivalents	(5.6)	(1.1)
Restricted cash	0.0	0.0
Accounts receivable, net	0.0	0.0
Notes receivable, net	0.0	0.0
Inventories	(16.1)	(19.2)
Prepaid expenses, deposits and other current assets	0.0	0.0
Property and equipment, net	(19.9)	(16.0)
Investment in subsidiaries	(5,008.8)	(4,871.4)
Goodwill	0.0	0.0
Intangible assets, net	0.0	0.0
Intercompany balances	(5,807.5)	(5,531.7)
Software, net	0.0	0.0
Other assets	(444.9)	(401.6)
Total assets	(11,302.8)	(10,841.0)
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	(7.2)	(1.1)
Long-term debt, excluding current portion	0.0	0.0
Other long-term liabilities	(443.2)	(401.6)
Intercompany balances	(5,807.5)	(5,531.7)
Stockholders' (deficit) equity	(5,044.9)	(4,906.6)
Total liabilities and stockholders' (deficit) equity	(11,302.8)	(10,841.0)
SGC (Parent and Issuer) | Reportable Legal Entities
Assets
Cash and cash equivalents	37.8	32.7
Restricted cash	0.0	0.0
Accounts receivable, net	0.0	0.0
Notes receivable, net	0.0	0.0
Inventories	0.0	0.0
Prepaid expenses, deposits and other current assets	5.3	11.6
Property and equipment, net	7.3	5.6
Investment in subsidiaries	3,045.4	3,000.7
Goodwill	0.0	0.0
Intangible assets, net	196.0	185.8
Intercompany balances	0.0	0.0
Software, net	77.6	74.7
Other assets	233.6	233.6
Total assets	3,603.0	3,544.7
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	98.9	100.5
Long-term debt, excluding current portion	0.0	248.7
Other long-term liabilities	189.1	159.0
Intercompany balances	5,310.2	4,972.2
Stockholders' (deficit) equity	(1,995.2)	(1,935.7)
Total liabilities and stockholders' (deficit) equity	3,603.0	3,544.7
SGI (Issuer) | Reportable Legal Entities
Assets
Cash and cash equivalents	1.0	1.7
Restricted cash	0.0	0.0
Accounts receivable, net	51.9	61.4
Notes receivable, net	0.0	0.0
Inventories	39.9	40.3
Prepaid expenses, deposits and other current assets	20.7	15.7
Property and equipment, net	93.7	98.4
Investment in subsidiaries	941.0	926.7
Goodwill	188.3	188.3
Intangible assets, net	37.3	37.5
Intercompany balances	5,594.2	5,415.1
Software, net	20.2	21.4
Other assets	281.0	236.5
Total assets	7,269.2	7,043.0
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	32.9	43.0
Other current liabilities	198.1	158.7
Long-term debt, excluding current portion	8,061.0	7,767.3
Other long-term liabilities	9.0	12.4
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	(1,031.8)	(938.4)
Total liabilities and stockholders' (deficit) equity	7,269.2	7,043.0
Guarantor Subsidiaries | Reportable Legal Entities
Assets
Cash and cash equivalents	0.0	0.0
Restricted cash	27.0	24.6
Accounts receivable, net	202.5	199.2
Notes receivable, net	103.6	94.4
Inventories	88.3	83.1
Prepaid expenses, deposits and other current assets	48.4	45.6
Property and equipment, net	347.0	369.3
Investment in subsidiaries	1,022.4	944.0
Goodwill	1,932.4	1,931.6
Intangible assets, net	1,323.2	1,343.0
Intercompany balances	0.0	0.0
Software, net	248.4	264.6
Other assets	57.1	50.8
Total assets	5,400.3	5,350.2
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	0.0	0.0
Other current liabilities	200.0	216.3
Long-term debt, excluding current portion	0.0	0.0
Other long-term liabilities	487.7	468.8
Intercompany balances	497.3	559.5
Stockholders' (deficit) equity	4,215.3	4,105.6
Total liabilities and stockholders' (deficit) equity	5,400.3	5,350.2
Non-current restricted cash	16.1	16.4
Non-Guarantor Subsidiaries | Reportable Legal Entities
Assets
Cash and cash equivalents	98.7	81.8
Restricted cash	0.1	0.1
Accounts receivable, net	209.1	234.4
Notes receivable, net	27.4	31.0
Inventories	141.4	138.1
Prepaid expenses, deposits and other current assets	38.8	41.2
Property and equipment, net	156.6	154.9
Investment in subsidiaries	0.0	0.0
Goodwill	785.4	768.5
Intangible assets, net	205.4	202.0
Intercompany balances	213.3	116.6
Software, net	49.3	48.4
Other assets	178.0	173.5
Total assets	2,103.5	1,990.5
Liabilities and stockholders' (deficit) equity
Current portion of long-term debt	6.4	6.3
Other current liabilities	156.4	168.7
Long-term debt, excluding current portion	7.4	8.9
Other long-term liabilities	71.9	67.2
Intercompany balances	0.0	0.0
Stockholders' (deficit) equity	1,861.4	1,739.4
Total liabilities and stockholders' (deficit) equity	2,103.5	1,990.5
Non-current restricted cash	$ 0.7	$ 0.7