Description of the Plan (Details) - EBP 001	12 Months Ended
Dec. 31, 2025 USD ($) h	Dec. 31, 2024 USD ($)
EBP, Description of Plan [Line Items]
Requisite service period, number of hours for temporary employees \| h	500
Requisite service period, number of years for temporary employees	2 years
Pretax, maximum annual compensation to total compensation, percentage	50.00%
Participant contribution, automatic deferral rate	3.00%
Participant contribution, automatic deferral rate, annual increase	1.00%
Employer supplemental contributions, percentage	3.00%
Requisite service period	2 years
Supplemental contributions, requisite service period	3 years
Forfeitures available to reduce future employer contributions	$ 91,884	$ 10,497
Forfeitures used to reduce employer contributions	$ 773,251	$ 809,000
Transfer from common trust fund into short-term investment, required holding period	90 days
Maximum borrowing, amount	$ 50,000
Maximum borrowing, to total account, percentage	50.00%
Basis spread on variable rate	2.00%
General Loan
EBP, Description of Plan [Line Items]
Minimum borrowing, amount	$ 500
Maximum borrowing term	5 years
Primary Residence Loan
EBP, Description of Plan [Line Items]
Minimum borrowing, amount	$ 1,000
Maximum borrowing term	15 years
EBP, Employer Matching Contribution, Scenario One
EBP, Description of Plan [Line Items]
Matching percentage	100.00%
Participant compensation matched, percentage	4.00%
EBP, Employer Matching Contribution, Scenario Two
EBP, Description of Plan [Line Items]
Matching percentage	50.00%
Participant compensation matched, percentage	2.00%
Maximum
EBP, Description of Plan [Line Items]
Participant contribution, automatic deferral rate	6.00%

EBP, Employer Contribution, Supplemental Contributions, Percentage

No definition available.

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- Definition

EBP, Investment, Transfer From Common Trust Fund Into Short-Term Investment, Required Holding Period

+ References

No definition available.

+ Details

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- Definition

EBP, Note Receivable From Participant, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Namespace Prefix:	gnw_
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Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Contribution, Automatic, Annual Increase In Deferral Rate

+ References

No definition available.

+ Details

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

- Definition

EBP, Participant Loan, Basis Spread On Variable Rate

+ References

No definition available.

+ Details

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

- Definition

EBP, Requisite Service Period

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Service Period For Temporary Employees, Number Of Hours

+ References

No definition available.

+ Details

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Namespace Prefix:	gnw_
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Balance Type:	na
Period Type:	duration

- Definition

EBP, Requisite Service Period For Temporary Employees, Number Of Years

+ References

No definition available.

+ Details

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Namespace Prefix:	gnw_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

EBP, Supplemental Contributions, Requisite Service Period

+ References

No definition available.

+ Details

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Namespace Prefix:	gnw_
Data Type:	xbrli:durationItemType
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage
Namespace Prefix:	us-gaap-ebp_
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Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanForfeitedNonvestedAccount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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