Summary of Unbilled Receivables (Detail) $ in Thousands	Sep. 30, 2018 USD ($)
Accounts Receivable and Unbilled Receivable [Line Items]
1 Year or Less	$ 155,964
1-2 Years	89,177
2-5 Years	79,752
Total	$ 324,893
Percentage of unbilled receivables, 1 Year or Less	48.00%
Percentage of unbilled receivables, 1-2 Years	27.00%
Percentage of unbilled receivables, 2-5 Years	25.00%
Total percentage of unbilled receivables	100.00%

Accounts receivable and unbilled receivable line items.

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- Definition

Unbilled Receivables Current and Non Current

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- Definition

Unbilled receivables current and non current percentage.

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No definition available.

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- Definition

Unbilled receivables not billable at balance sheet date amount expected to be collected within year one and two.

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No definition available.

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- Definition

Unbilled receivables not billable at balance sheet date amount expected to be collected within year two and five.

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No definition available.

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- Definition

Unbilled receivables not billable at balance sheet date expected percentage to be collected within one year.

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No definition available.

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- Definition

Unbilled receivables not billable at balance sheet date expected percentage to be collected within year one and two.

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No definition available.

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- Definition

Unbilled receivables not billable at balance sheet date expected percentage to be collected within year two and five.

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No definition available.

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- Definition

Amount of receivables under long-term contracts that have not been billed and were not billable that are expected to be collected in the next fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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