Significant Accounting Policies - Practical expedients (Details)	12 Months Ended
Dec. 31, 2020
Exemptions and Practical Expedients Applied or Elected
Practical Expedient, unfulfilled performance obligation	True
Practical Expedient, relative to costs of obtaining a contract	true
Practical Expedient, relative to estimation of variable consideration	true
Practical Expedient, relative to required remaining performance obligations disclosure	true

No definition available.

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- Definition

Indicates (true false) whether practical expedient was elected to recognize incremental cost of obtaining contract as expense when incurred if amortization period would have been one year or less.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL51790836-203054

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130569-203045

+ Details

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- Definition

Indicates (true false) whether practical expedient was elected not to disclose amount of transaction price allocated to remaining performance obligation and explanation of expected timing of revenue recognition for reporting period presented prior to date of initial application under retrospective method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 65
-Paragraph 1
-Subparagraph (f)(3)
-URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048

+ Details

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- Definition

Description of consideration that is not included in transaction price and not allocated to remaining performance obligation. Includes, but is not limited to, variable consideration that is constrained.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

+ Details

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Balance Type:	na
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- Definition

Indicates (true false) whether optional exemption for variable consideration was applied not to disclose amount of transaction price allocated to and timing of revenue recognition for remaining performance obligation.

+ References

+ Details

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