Amount of liability recognized arising from addition of contingent earn-out obligations.

No definition available.

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Period Type:	duration

- Definition

Amount of decrease in the value of a contingent consideration liability arising upon payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	osis_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The amount of increase or decrease in the foreign currency translation adjustment.

+ References

No definition available.

+ Details

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Namespace Prefix:	osis_
Data Type:	xbrli:monetaryItemType
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- Definition

The contingent liability as of the balance sheet date to an individual under a deferred compensation arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	osis_
Data Type:	xbrli:monetaryItemType
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- Definition

Maximum period the entity is required to make the payment after a date under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e7008-128479

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_LossContingencyAccrualDisclosuresAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Amount of cash outflow, made soon after acquisition date of business combination, to settle contingent consideration liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(9))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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COMMITMENTS AND CONTINGENCIES - Contingent Acquisition Obligations (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 31, 2017	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Contingent Acquisition Obligations
Payments for contingent consideration		$ 1,900	$ 1,000
Beginning fair value, June 30, 2021		19,431
Addition of contingent earnout obligations		14,609
Foreign currency translation adjustment		(515)
Changes in fair value for contingent earnout obligations		(5,145)
Payments on contingent earnout obligations		(168)
Ending fair value, June 30, 2022		28,212	19,431
Legal Proceedings
Legal fees, settlements and related costs, net		5,104	465	$ (3,572)
Prepaid expenses and other assets		40,062	$ 43,930
Certain Acquisitions
Contingent Acquisition Obligations
Remaining maximum amount of contingent consideration		$ 52,200
Mr. Chopra, Chief Executive Officer \| Deferred bonus
Indemnifications and Certain Employment-Related Contingencies
Bonus payment on or within 45 days of January 1, 2024 contingent upon continued employment through that date	$ 13,500
Maximum number of days after January 1, 2024, bonus payment due	45 days