Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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

- Definition

The principal amount of additional debt that can be borrowed under the debt instrument amendment.

+ References

No definition available.

+ Details

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Namespace Prefix:	xlo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Additional interest rate percentage per annum to be applied to outstanding loan balance and paid in event of default.

+ References

No definition available.

+ Details

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Namespace Prefix:	xlo_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of fee paid under the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	xlo_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of additional term loans entity may request under the terms of the agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	xlo_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Details

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- Details

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Loan and Security Agreement - Description (Details) - Loan Agreement and Amended Loan Agreement $ in Millions	1 Months Ended
	Oct. 31, 2021 USD ($)	Nov. 30, 2019 USD ($) loan	Sep. 30, 2022
Loan and security agreement
Borrowed amount		$ 10.0
Additional borrowing capacity		$ 10.0
Interest rate at end of period (as a percent)			6.50%
Fee paid upon closing of IPO	$ 0.8
Additional interest rate upon event of default (as a percent)		5.00%
Minimum
Loan and security agreement
Number of additional term loans that may be requested \| loan		1
Stated interest rate		4.75%
Prime rate
Loan and security agreement
Basis spread (as percent)		0.25%