IDR stands for the Indian Depository Receipts.
These receipts are issued against the underlying equity of the Issuing Company.
The foreign Companies deposit shares with Indian depository and in exchange of it the Indian depository will issue receipts to the investors for the money which they have invested.
Standard Chartered PLC was the first company to issue IDRs. They raised around INR 2490 crore by selling 24 crore IDR’s.