ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2017 CNY (¥)
ACCUMULATED OTHER COMPREHENSIVE INCOME
Beginning balance		¥ 5,363,184	¥ 5,201,004	¥ 6,151,017
Other comprehensive income (loss)	$ (1,160)	(8,075)	88,652	(120,963)
Ending balance	751,478	5,231,628	5,363,184	5,201,004
Accumulated Translation Adjustment
ACCUMULATED OTHER COMPREHENSIVE INCOME
Beginning balance		85,979	(2,673)	118,290
Other comprehensive income (loss)		(8,075)	88,652	(120,963)
Ending balance	$ 11,190	¥ 77,904	¥ 85,979	¥ (2,673)

Amount after tax and reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580

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