Represents the number of Vertical/Trigen shareholders with whom the company has entered into a consulting agreement.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Amount of compensation rate per month incurred under the consulting agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	osmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the term of consulting agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	osmt_
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Balance Type:	na
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Related Parties (Details)	1 Months Ended	12 Months Ended
Related Parties (Details)	Nov. 30, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2016 USD ($) shareholder
Shareholder
Related Party Transaction [Line Items]
Accrued liability			$ 100,000
Related party expenses		$ 100,000	1,100,000
Avista
Related Party Transaction [Line Items]
Accrued liability			0
Related party expenses		1,900,000	0
Amount per agreement	$ 2,400,000
Vertical/Trigen
Related Party Transaction [Line Items]
Term of consulting agreement				2 years
Number of Vertical/Trigen shareholders \| shareholder				2
Compensation rate per month				$ 20,833
Related Party Lessor [Member]
Related Party Transaction [Line Items]
Related party expenses		200,000	$ 200,000
Maximum \| Shareholder
Related Party Transaction [Line Items]
Accrued liability		100,000
Maximum \| Avista
Related Party Transaction [Line Items]
Accrued liability		$ 100,000