INCOME TAX - Unrecognized Income Tax Benefits - Reconciliation (Details) ₽ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2019 RUB (₽)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 RUB (₽)	Dec. 31, 2017 RUB (₽)
Reconciliation of the total amounts of unrecognized income tax benefits
Balance at the beginning of the period	₽ 239	$ 3.0	₽ 290	₽ 580
Increases related to prior years tax positions	155	2.0	9	98
Decreases related to prior years tax positions	(11)	(0.1)	(111)	(13)
Increases related to current year tax positions	56	0.7	51	41
Settlements				(416)
Balance at the end of the period	₽ 439	$ 5.6	₽ 239	₽ 290

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=116821951&loc=SL37586934-109318

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-Section 50
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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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- Definition

Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 15A
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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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