SUMMARY OF PRINCIPAL ACCOUNTING POLICIES - Allowance for doubtful receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Allowance for doubtful receivables
Receivable from Sinosure recorded in prepaid expenses and other current assets	$ 164	$ 9

Represents the amount of receivable from China Export & Credit Insurance Corporation recorded in prepaid expenses and other current assets.

No definition available.

Name:	csiq_InsuranceForBadDebtLossReceivableCurrent
Namespace Prefix:	csiq_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant