Related Party Transactions - Summary of Significant Balances, Transactions and Payments with Related Parties and Affiliates (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Related party accounts receivable	$ 976		$ 736
MegaChips
Related Party Transaction [Line Items]
Related party accounts receivable	976		736
Property and equipment, net			$ 209
Sales through distribution agreement	1,855	$ 1,146
License expense		68
Commission expense	77	47
Cash paid for commissions	77	47
Cash paid for licenses		17
Affliates
Related Party Transaction [Line Items]
Consulting fees	87	117
Cash paid for consulting fees	$ 87	$ 117

Cash paid for commission related party.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Cash paid for consulting fees related party.

+ References

No definition available.

+ Details

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

- Definition

Cash paid for license related party.

+ References

No definition available.

+ Details

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

- Definition

Commission expense related party.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

License expense related party.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Property and equipment, net related parties, noncurrent.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

+ 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
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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Period Type:	instant

- Definition

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

+ 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
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Balance Type:	debit
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- 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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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874292-224272

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-Name Accounting Standards Codification
-Topic 220
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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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