LOANS AND LEASES (Schedule of Modified as Troubled Debt Restructurings Subsequently Defaulted) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2022 USD ($) Loan	Sep. 30, 2021 USD ($) Loan
Number of Subsequently Defaulted Loans \| Loan	1	1
Pre-Modification Outstanding Subsequently Defaulted Recorded Investment		$ 221
Post-Modification Outstanding Subsequently Defaulted Recorded Investment		$ 221
Subsequently Defaulted Recorded Investment	$ 145
Residential Portfolio Segment [Member] \| Primary Residential Mortgages [Member]
Number of Subsequently Defaulted Loans \| Loan	1	1
Pre-Modification Outstanding Subsequently Defaulted Recorded Investment		$ 221
Post-Modification Outstanding Subsequently Defaulted Recorded Investment		$ 221
Subsequently Defaulted Recorded Investment	$ 145

Financing receivable modifications post modification subsequent default recorded investment.

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- Definition

Financing receivable modifications pre modification subsequent default recorded investment.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgc_
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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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