Cash, Cash Equivalents and Marketable Securities Available for Sale - Summary of Cash, Cash Equivalents and Marketable Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Cash and Cash Equivalents
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	$ 106,426	$ 90,023
Fair Value	106,426	90,023
Cash and Cash Equivalents \| Cash
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	77,525	71,610
Fair Value	77,525	71,610
Cash and Cash Equivalents \| Money market funds
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	22,102	13,813
Fair Value	22,102	13,813
Cash and Cash Equivalents \| Bank Time Deposits
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	6,799	4,600
Fair Value	6,799	4,600
Long-term Marketable Securities \| Marketable securities
Cash, cash equivalents and marketable securities [Line Items]
Trading Securities, Cost	17,193	14,313
Debt Securities, Trading, and Equity Securities, FV-NI	$ 20,222	$ 18,059

Cash, cash equivalents and marketable securities

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Cost of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

No definition available.

+ Details

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