Balance Sheet Details Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Balance Sheet Details [Abstract]
Contract assets	$ 85,118	$ 79,407
Prepaid expenses	55,170	49,051
Capitalized contract acquisition costs	27,752	28,228
Other	20,164	26,188
Other Assets, Current	$ 188,204	$ 182,874

Balance Sheet Details [Abstract]

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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- Definition

Amount of current assets classified as other.

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Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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