Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017
Payables and Accruals [Abstract]
Compensation	$ 103,991	$ 159,951
Accrued interest payable	21,733	26,285
Cost of revenue related liabilities	22,066	20,124
Consulting and professional fees	19,274	12,649
Facilities related liabilities	5,540	7,158
Sales and marketing incentives	4,190	3,655
Sales and other taxes payable	3,190	3,125
Other	13,422	12,954
Total	$ 193,406	$ 245,901

Accrued Cost of Revenue Related Liabilities, Current

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- Definition

Facilities related liabilities

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No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for the marketing, trade and selling of the entity's goods and services. Marketing costs would include expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services; costs of public relations and corporate promotions; and obligations incurred and payable for sales discounts, rebates, price protection programs, etc. offered to customers and under government programs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

No definition available.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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