Proceeds from collection of accounts receivable.

No definition available.

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- Definition

Proceeds from sale of accounts receivable.

+ References

No definition available.

+ Details

Name:	omi_ProceedsFromSaleOfAccountsReceivables
Namespace Prefix:	omi_
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- Definition

Summary Of Significant Accounting Policies [Line Items]

+ References

No definition available.

+ Details

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- Definition

Amount of uncollected accounts receivables sold or removed as of date.

+ References

No definition available.

+ Details

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Namespace Prefix:	omi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of decrease from sale of accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-11

+ Details

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Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479405/805-10-25-23

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense incurred and directly related to generating revenue by lessor from operating lease of rented property and equipment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(2)(c))
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

+ Details

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

- Definition

Amount of gain (loss) on sale of accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-18

+ Details

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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-8

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

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Namespace Prefix:	us-gaap_
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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- Details

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Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Mar. 14, 2023 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| segment			2
Rotech Healthcare Holdings Inc
Summary Of Significant Accounting Policies [Line Items]
Acquisition-related charges	$ 6.5		$ 10.2
Apria Inc
Summary Of Significant Accounting Policies [Line Items]
Acquisition-related charges		$ 9.4		$ 11.9
Rental Equipment
Summary Of Significant Accounting Policies [Line Items]
Revenue related to equipment	148.0	158.0	442.0	458.0
Master Receivables Purchase Agreement
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	13.2		13.2		$ 13.5
Uncollected accounts receivable	121.0		121.0		$ 124.0
Net cash proceeds	542.0	482.0	1,600.0	894.0
Cash proceeds from sale of accounts receivable	538.0	478.0	1,600.0	888.0
Cash proceeds from collection of accounts receivable	550.0	508.0	1,600.0	805.0
Master Receivables Purchase Agreement \| Other Operating Income (Expense)
Summary Of Significant Accounting Policies [Line Items]
Losses on sale of accounts receivable	$ (3.6)	$ (3.5)	$ (10.8)	$ (7.1)
Master Receivables Purchase Agreement \| Maximum
Summary Of Significant Accounting Policies [Line Items]
Uncollected accounts receivable						$ 200.0