Financing receivable increase in individually evaluated substandard loans.

No definition available.

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- Definition

Amount of investment in specific reserve accrual financing receivables (after modification) modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing receivable modifications unfunded commitments.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing receivable substandard and individually evaluated loan.

+ References

No definition available.

+ Details

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

- Definition

Loan receivable, validate risk ratings performed for criticized and classified rated borrowers with relationship exposure, value.

+ References

No definition available.

+ Details

Name:	pgc_LoanReceivableValidateRiskRatingsPerformedForCriticizedAndClassifiedRatedBorrowersWithRelationshipExposureValue
Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable, validate risk ratings performed for large sample of borrowers with relationship, value.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable, validate risk ratings performed for large sample or new lending to existing relationships, value.

+ References

No definition available.

+ Details

Name:	pgc_LoanReceivableValidateRiskRatingsPerformedForLargeSampleOrNewLendingToExistingRelationshipsValue
Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable validate risk ratings performed for leveraged loans, value.

+ References

No definition available.

+ Details

Name:	pgc_LoanReceivableValidateRiskRatingsPerformedForLeveragedLoansValue
Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable validate risk ratings performed for new federal reserve board regulation loan commitments value.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable validate risk ratings performed for no borrower with commitments, value.

+ References

No definition available.

+ Details

Name:	pgc_LoanReceivableValidateRiskRatingsPerformedForNoBorrowerWithCommitmentsValue
Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Loan receivable, validate risk ratings performed for Small sample of borrowers with relationship, value.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

+ Details

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

- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-14

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 80
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-80

+ Details

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

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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LOANS AND LEASES - Additional Information (Details)	3 Months Ended	9 Months Ended		12 Months Ended
LOANS AND LEASES - Additional Information (Details)	Sep. 30, 2022 USD ($) Loan	Sep. 30, 2023 USD ($) Loan	Sep. 30, 2022 USD ($) Loan	Dec. 31, 2022 USD ($)
Financing Receivable Recorded Investment Past Due [Line Items]
Loan receivable, validate risk ratings performed for large sample or new lending to existing relationships		$ 1,000,000
Loan receivable, validate risk ratings performed for criticized and classified rated borrowers with relationship exposure, value		500,000
Loan receivable, validate risk ratings performed for new federal reserve board regulation "O" loan commitments, value		1,000,000
Loan receivable validate risk ratings performed for leveraged loans, value		1,000,000
Loan receivable validate risk ratings performed for no borrower with commitments, value		500,000
Troubled debt restructurings specific reserves	$ 2,400,000		$ 2,400,000
Troubled debt restructurings unfunded commitments		0
Number of Loans \| Loan	0		1
Troubled debt restructuring, payments default, number of loans \| Loan			1
Substandard [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Financing receivable individually evaluated loan		70,000,000		$ 14,700,000
Substandard [Member] \| Multifamily Property [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Financing receivable increase in individually evaluated substandard loans		$ 18,900,000
Number of Loans \| Loan		3
Substandard [Member] \| Equipment Financing Lease [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Financing receivable increase in individually evaluated substandard loans		$ 33,400,000
Number of Loans \| Loan		2
Minimum [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loan receivable, validate risk ratings performed for large sample of borrowers with relationship, value		$ 1,000,000
Maximum [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loan receivable, validate risk ratings performed for small sample of borrowers with relationship, value		$ 1,000,000