The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

No definition available.

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INVESTMENTS IN AFFILIATES (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Aug. 31, 2013
Other investments
Carrying Value	$ 414,215	$ 368,459
Gaochuangte
Other investments
Carrying Value		$ 7,049
Ownership percentage		40.00%
CSI Skypower
Other investments
Carrying Value		$ 3,749
Ownership percentage		50.00%	50.00%
Tranquillity
Other investments
Carrying Value	$ 145,795	$ 143,951
Ownership percentage	49.00%	49.00%
Garland
Other investments
Carrying Value	$ 120,247	$ 118,641
Ownership percentage	49.00%	49.00%
Roserock
Other investments
Carrying Value	$ 77,053	$ 30,870
Ownership percentage	49.00%	49.00%
Suzhou Financial Leasing Co., Ltd.
Other investments
Carrying Value	$ 14,129	$ 12,974
Ownership percentage	6.00%	6.00%
Pirapora Solar Holding S.A.
Other investments
Carrying Value	$ 6,551	$ 13,775
Ownership percentage	20.00%	20.00%
Canadian Solar Infrastructure Fund, Inc
Other investments
Carrying Value	$ 23,866
Ownership percentage	14.76%
Others
Other investments
Carrying Value	$ 26,574	$ 37,450
Others \| Minimum
Other investments
Ownership percentage	21.00%	21.00%
Others \| Maximum
Other investments
Ownership percentage	49.00%	49.00%