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, 2020	Sep. 30, 2019
Cash and Cash Equivalents
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	$ 157,394	$ 106,426
Fair Value	157,394	106,426
Cash and Cash Equivalents \| Cash
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	122,119	77,525
Fair Value	122,119	77,525
Cash and Cash Equivalents \| Money market funds
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	35,275	22,102
Fair Value	35,275	22,102
Cash and Cash Equivalents \| Bank Time Deposits
Cash, cash equivalents and marketable securities [Line Items]
Amortized Cost	0	6,799
Fair Value	0	6,799
Long-term Marketable Securities \| Marketable securities
Cash, cash equivalents and marketable securities [Line Items]
Trading Securities, Cost	20,195	17,193
Debt Securities, Trading, and Equity Securities, FV-NI	$ 25,513	$ 20,222

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=120398452&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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