Fair Value Measurement - Summary of Fair Value of Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2021	Jun. 30, 2020
Assets
Cash equivalents	$ 1,170,304	$ 20,075
Short-term investments	512,520	123,974
Funds held for customers	880,704	1,062,493
Total assets measured at fair value	2,563,528	1,206,542
Municipal Bonds
Assets
Funds held for customers	34,930
Money Market Funds
Assets
Cash equivalents	1,126,692	20,075
Level 1
Assets
Cash equivalents	1,126,692	20,075
Short-term investments	84,215	28,368
Funds held for customers	11,570	406,302
Total assets measured at fair value	1,222,477	454,745
Level 1 \| Money Market Funds
Assets
Cash equivalents	1,126,692	20,075
Level 2
Assets
Cash equivalents	43,612
Short-term investments	428,305	95,606
Funds held for customers	869,134	656,191
Total assets measured at fair value	1,341,051	751,797
Level 2 \| Municipal Bonds
Assets
Funds held for customers	34,930
Certificates of Deposit
Assets
Short-term investments	3,772
Funds held for customers	222,181	85,953
Certificates of Deposit \| Level 2
Assets
Short-term investments	3,772
Funds held for customers	222,181	85,953
Corporate Bonds
Assets
Cash equivalents	43,612
Short-term investments	396,201	71,131
Funds held for customers	489,158	493,879
Corporate Bonds \| Level 2
Assets
Cash equivalents	43,612
Short-term investments	396,201	71,131
Funds held for customers	489,158	493,879
U.S. Treasury Securities
Assets
Short-term investments	84,215	28,368
Funds held for customers	10,000	48,952
U.S. Treasury Securities \| Level 1
Assets
Short-term investments	84,215	28,368
Funds held for customers	10,000	48,952
Asset-Backed Securities
Assets
Short-term investments	28,332	24,475
Funds held for customers	14,994
Asset-Backed Securities \| Level 2
Assets
Short-term investments	28,332	24,475
Funds held for customers	14,994
Restricted Cash Equivalents
Assets
Funds held for customers	109,441	433,709
Restricted Cash Equivalents \| Level 1
Assets
Funds held for customers	1,570	357,350
Restricted Cash Equivalents \| Level 2
Assets
Funds held for customers	$ 107,871	$ 76,359

Funds held for customers debt securities fair value disclosure.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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