Subsequent Events - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended	0 Months Ended
Sep. 30, 2014	Oct. 22, 2014 Subsequent Events [Member] Credit Suisse [Member]	Oct. 09, 2014 Subsequent Events [Member] Auxilium [Member]
Subsequent Event [Line Items]
Merger Agreement termination date	Oct. 08, 2014
Terminated Merger Transaction with Auxilium			$ 28.4
Fees paid		$ 5.7

Fee received by QLT from Auxilium Pharmaceuticals, Inc. in connection with the termination of the Merger Agreement.

No definition available.

Name:	qlti_FeeReceivedInConnectionWithTerminationOfMergerAgreement
Namespace Prefix:	qlti_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration