Lessee operating lease extension term.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Manufacturing facility number of square feet.

+ References

No definition available.

+ Details

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Namespace Prefix:	sana_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating lease expiration beginning month and year.

+ References

No definition available.

+ Details

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Namespace Prefix:	sana_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating lease expiration ending month and year.

+ References

No definition available.

+ Details

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Namespace Prefix:	sana_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating lease, number of additional extensions.

+ References

No definition available.

+ Details

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Namespace Prefix:	sana_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

+ Details

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

- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

+ Details

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Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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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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Subsequent Events - Additional Information (Details) $ in Thousands	1 Months Ended	6 Months Ended
	Jul. 31, 2021 USD ($) ft² Extension	Jun. 30, 2021 USD ($)	Jul. 31, 2023 USD ($)
Subsequent Event [Line Items]
Expiration Dates, Beginning		2024-04
Expiration Dates, Ending		2030-04
Base rent		$ 111,960
Fremont, CA \| Scenario Forecast \| Letter of Credit
Subsequent Event [Line Items]
Line of credit amount			$ 500
Fremont, CA \| Subsequent Event
Subsequent Event [Line Items]
Number of square feet to lease \| ft²	163,193
Expiration Dates, Beginning	2021-07
Expiration Dates, Ending	2031-11
Lessee, operating lease, existence of option to extend [true false]	true
Lessee, operating lease, option to extend	option to extend for up to two additional five-year terms
Operating lease extension term	5 years
Base rent	$ 28,600
Fremont, CA \| Subsequent Event \| Letter of Credit
Subsequent Event [Line Items]
Letter of credit amount	$ 6,400
Fremont, CA \| Subsequent Event \| Maximum
Subsequent Event [Line Items]
Number of additional extensions permitted \| Extension	2