CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable, current	$ 6,560	$ 4,285
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares outstanding	63,811,000	64,371,000
Common stock, shares issued	63,811,000	64,371,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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