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

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The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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.

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INVESTMENTS IN AFFILIATES - Other investments (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2020	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other investments
Cash consideration for acquisition of the entity			$ 17,758	$ 7,684	$ 11,036
Equity in earnings (loss) of unconsolidated investees			10,779	28,948	5,908
Impairment loss of investment			$ 24,060	$ 0	$ 5,738
Gain or loss on sale of equity investments	$ 13,140
Suzhou Financial Leasing Co., Ltd.
Other investments
Ownership percentage	6.00%		6.00%	6.00%
Canadian Solar Infrastructure Fund, Inc
Other investments
Ownership percentage	14.66%		14.66%	14.66%
Now, Inc.
Other investments
Ownership percentage		10.00%
Impairment loss of investment		$ 700