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

No definition available.

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- 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
Balance Type:	credit
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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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Namespace Prefix:	osis_
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Balance Type:	na
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- References

No definition available.

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Name:	osis_EmploymentRelatedContingenciesAbstract
Namespace Prefix:	osis_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationContingentConsiderationArrangementsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-4

+ Details

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

- 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
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

+ Details

Name:	us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479668/805-30-25-6

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 35
-Paragraph 1
-Subparagraph (b)
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479613/805-30-35-1

+ Details

Name:	us-gaap_BusinessCombinationContingentConsiderationLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Subparagraph (d)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-13

+ Details

Name:	us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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, 2023	Jun. 30, 2022	Jun. 30, 2021
Contingent Acquisition Obligations
Payments for contingent consideration		$ 3,400	$ 1,900	$ 1,000
Beginning fair value, June 30, 2022		28,212
Addition of contingent earnout obligations		5,506
Foreign currency translation adjustment		27
Changes in fair value for contingent earnout obligations		(11,901)
Payments on contingent earnout obligations		(663)
Ending fair value, March 31, 2023		21,181	$ 28,212
Certain Acquisitions
Contingent Acquisition Obligations
Remaining maximum amount of contingent consideration		$ 55,300
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