Risk free rate description.

No definition available.

Name:	qtnt_RiskFreeRateDescription
Namespace Prefix:	qtnt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based compensation arrangement by share based payment award, consecutive trading days in which target price must exceed threshold.

+ References

No definition available.

+ Details

Name:	qtnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardConsecutiveTradingDaysInWhichTargetPriceMustExceedThreshold
Namespace Prefix:	qtnt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based compensation arrangement by share based payment Award, period in which target must be achieved, end date.

+ References

No definition available.

+ Details

Name:	qtnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodInWhichTargetMustBeAchievedEndDate
Namespace Prefix:	qtnt_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based compensation arrangement by share based payment award period in which target must be achieved, start date.

+ References

No definition available.

+ Details

Name:	qtnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodInWhichTargetMustBeAchievedStartDate
Namespace Prefix:	qtnt_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=qtnt_TimeBasedVestingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=qtnt_MilestoneVestingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=qtnt_MultiYearPerformanceBasedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OptionIndexedToIssuersEquityEquityAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Share-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Thousands			3 Months Ended		6 Months Ended
	Aug. 09, 2017 $ / shares	May 24, 2017 $ / shares	Sep. 30, 2017 USD ($) $ / shares shares	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) d $ / shares shares	Sep. 30, 2016 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense \| $			$ 1,187	$ 1,083	$ 2,472	$ 1,981
Risk-free interest rate, Description					Risk-Free Interest Rate. The risk-free interest rate is based on the US Treasury 10-year bond yield in effect at the time of grant.
Grant date fair value (per share)	$ 5.41	$ 7.58
Restricted Stock Units (RSUs) [Member] \| Time Based Vesting [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding \| shares			294,063		294,063
Weighted average remaining vesting period					15 months
Restricted Stock Units (RSUs) [Member] \| Milestone Vesting [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding \| shares			290,000		290,000
Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $22 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding \| shares			166,000		166,000
Consecutive trading days in which price must exceed threshold \| d					20
Period in which the target must be achieved, start date					Apr. 01, 2019
Period in which the target must be achieved, end date					Dec. 31, 2019
Grant date fair value (per share)					$ 3.20
Award vesting description					166,000 MRSUs were awarded on May 24, 2017, which will vest if the volume weighted average price of the Company’s ordinary shares exceeds $22 for a continuous twenty day period between April 1, 2019 and December 31, 2019.
Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $60 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding \| shares			114,500		114,500
Consecutive trading days in which price must exceed threshold \| d					20
Period in which the target must be achieved, start date					Apr. 01, 2018
Period in which the target must be achieved, end date					Dec. 31, 2018
Award vesting description					114,500 MRSUs, which will vest between April 1, 2018 and December 31, 2018 if the Company’s ordinary share price exceeds $60 for 20 consecutive days in this period.
Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $40 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding \| shares			127,000		127,000
Consecutive trading days in which price must exceed threshold \| d					20
Period in which the target must be achieved, start date					Apr. 01, 2018
Period in which the target must be achieved, end date					Dec. 31, 2018
Award vesting description					127,000 MRSUs, which will vest between April 1, 2018 and December 31, 2018 if the Company’s ordinary share price exceeds $40 for 20 consecutive days in this period.
Employee Stock Option [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					1 year
Employee Stock Option [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					3 years
Ordinary Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Company's closing share price			$ 4.93		$ 4.93
Ordinary Shares [Member] \| Minimum [Member] \| Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $22 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average price of shares			22		22
Ordinary Shares [Member] \| Minimum [Member] \| Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $60 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average price of shares			60		60
Ordinary Shares [Member] \| Minimum [Member] \| Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $40 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average price of shares			$ 40		$ 40