Related Party Transactions (Details) - USD ($)		12 Months Ended
	Dec. 21, 2012	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Oct. 03, 2012	Oct. 03, 2011
Silver Lake Management Company L.L.C.
Related Party Transaction [Line Items]
Management fee		$ 7,000,000		$ 7,000,000	$ 7,000,000
The Sponsors
Related Party Transaction [Line Items]
Cost of goods and services sold		11,000,000	$ 8,000,000	1,000,000
Revenue from related parties		30,000,000	27,000,000	$ 6,000,000
CommericalRealEstateServicesFirm [Member]
Related Party Transaction [Line Items]
Cost of goods and services sold		4,000,000
Tpg Capital
Related Party Transaction [Line Items]
Management Fee, current year reduction			1,325,000
Management Fee, next fiscal year and thereafter reduction		800,000
Messrs. Mohebbi and Rittenmeyer [Member]
Related Party Transaction [Line Items]
Management fee		$ 800,000
Unsecured Debt | 10.125%/10.875% senior unsecured PIK toggle notes due 2015
Related Party Transaction [Line Items]
Debt instrument stated rate				10.875%
Unsecured Debt | 10.125%/10.875% senior unsecured PIK toggle notes due 2015 | Tpg Capital
Related Party Transaction [Line Items]
Repayments of Debt and Capital Lease Obligations	$ 22,000,000
Secured Debt | Senior secured notes 9 percent
Related Party Transaction [Line Items]
Debt instrument stated rate	9.00%
Secured Debt | Senior Secured Term B-1 Loans | Silver Lake Partners
Related Party Transaction [Line Items]
Payments for loans receivable				$ 5,000,000
Secured Debt | Senior Secured Term B-1 Loans | Tpg Capital
Related Party Transaction [Line Items]
Payments for loans receivable				$ 23,000,000
Secured Debt | Senior Secured Term B-5 Loans
Related Party Transaction [Line Items]
Repayments of Debt and Capital Lease Obligations	$ 284,000,000
Debt instrument stated rate				10.50%
Secured Debt | Senior Secured Term B-5 Loans | Silver Lake Partners
Related Party Transaction [Line Items]
Payments for loans receivable			1,000,000
NES acquisition | Series A Preferred Stock | Silver Lake Partners
Related Party Transaction [Line Items]
Preferred shares issued		38,864.13
NES acquisition | Series A Preferred Stock | Tpg Capital
Related Party Transaction [Line Items]
Preferred shares issued		38,864.13
NES acquisition | Series B Preferred Stock | Silver Lake Partners
Related Party Transaction [Line Items]
Preferred shares issued		32,649
NES acquisition | Series B Preferred Stock | Tpg Capital
Related Party Transaction [Line Items]
Preferred shares issued		32,649
Unified Communications Solutions Provider
Related Party Transaction [Line Items]
Related parties notes receivable						$ 10,000,000
Unified Communications Solutions Provider | Advance to Parent due January 24, 2019
Related Party Transaction [Line Items]
Stated interest rate percentage notes receivable, related parties							1.65%
Maximum | Expert Global Solutions
Related Party Transaction [Line Items]
Revenue from related parties		$ 8,000,000	9,000,000	$ 9,000,000
Maximum | Intuit
Related Party Transaction [Line Items]
Revenue from related parties		1,000,000	2,000,000	2,000,000
Maximum | Ciena
Related Party Transaction [Line Items]
Cost of goods and services sold				1,000,000	$ 1,000,000
Maximum | Accenture [Member]
Related Party Transaction [Line Items]
Cost of goods and services sold		1,000,000	1,000,000	4,000,000
Revenue from related parties		1,000,000	1,000,000	3,000,000
Maximum | C3 [Member]
Related Party Transaction [Line Items]
Revenue from related parties		1,000,000	2,000,000	1,000,000
Maximum | Sungard [Member]
Related Party Transaction [Line Items]
Cost of goods and services sold		1,000,000
Maximum | Tenet Healthcare [Member]
Related Party Transaction [Line Items]
Revenue from related parties		1,000,000	1,000,000	$ 1,000,000
Maximum | Xirrus [Member]
Related Party Transaction [Line Items]
Cost of goods and services sold		$ 10,000,000	$ 5,000,000