REGULATORY CAPITAL (Schedule of Regulatory Capital Amounts and Ratios) (Details) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
The Bank [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 801,365	$ 773,083
Total Capital (to risk-weighted assets) ratio	0.1475	0.1473
Minimum Capital required to be well-capitalized	$ 543,234	$ 525,001
Minimum Capital required to be well-capitalized, ratio	0.1000	0.1000
Minimum amount of capital for adequacy purposes	$ 434,587	$ 420,001
Minimum amount of capital for adequacy purposes, ratio	0.0800	0.0800
Tier I Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 733,389	$ 707,446
Tier 1 Capital (to risk-weighted assets) ratio	0.1350	0.1348
Minimum Tier 1 Capital required to be well-capitalized	$ 434,587	$ 420,001
Minimum Tier 1 Capital required to be well-capitalized, ratio	0.0800	0.0800
Minimum amount of Tier 1 Capital for adequacy purposes	$ 325,940	$ 315,000
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0600	0.0600
Common equity tier I
Common equity tier 1 (to risk-weighted assets)	$ 733,383	$ 707,434
Common equity tier I (to risk-weighted assets) ratio	0.1350	0.1347
Minimum Common equity tier I required to be well-capitalized	$ 353,102	$ 341,250
Minimum common equity tier I required to be well-capitalized, ratio	6.50%	6.50%
Minimum amount of common equity tier I for adequacy purposes	$ 244,455	$ 236,250
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier I Leverage Capital (to average assets)
Tier 1 Capital(to average assets)	$ 733,389	$ 707,446
Tier 1 Capital (to average assets) ratio	0.1057	0.1083
Minimum Tier 1 Capital required to be well-capitalized	$ 347,006	$ 326,507
Minimum Tier 1 Capital required to be well-capitalized, ratio	0.0500	0.0500
Minimum amount of Tier 1 Capital for adequacy purposes	$ 277,605	$ 261,205
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0400	0.0400
The Bank [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 570,396	$ 551,251
Minimum amount of capital for adequacy purposes, ratio	0.1050	0.1050
Tier I Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 461,749	$ 446,251
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0850	0.0850
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 380,264	$ 367,500
Minimum amount of common equity tier I for adequacy purposes, ratio	7.00%	7.00%
Tier I Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 277,605	$ 261,205
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0400	0.0400
Parent Company [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 806,404	$ 785,413
Total Capital (to risk-weighted assets) ratio	0.1484	0.1495
Minimum amount of capital for adequacy purposes	$ 434,830	$ 420,377
Minimum amount of capital for adequacy purposes, ratio	0.0800	0.0800
Tier I Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 625,830	$ 600,444
Tier 1 Capital (to risk-weighted assets) ratio	0.1151	0.1143
Minimum amount of Tier 1 Capital for adequacy purposes	$ 326,123	$ 315,283
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0600	0.0600
Common equity tier I
Common equity tier 1 (to risk-weighted assets)	$ 625,824	$ 600,432
Common equity tier I (to risk-weighted assets) ratio	0.1151	0.1143
Minimum amount of common equity tier I for adequacy purposes	$ 244,592	$ 236,462
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier I Leverage Capital (to average assets)
Tier 1 Capital(to average assets)	$ 625,830	$ 600,444
Tier 1 Capital (to average assets) ratio	0.0901	0.0919
Minimum amount of Tier 1 Capital for adequacy purposes	$ 277,710	$ 261,358
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0400	0.0400
Parent Company [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 570,715	$ 551,745
Minimum amount of capital for adequacy purposes, ratio	0.1050	0.1050
Tier I Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 462,007	$ 446,651
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0850	0.0850
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 380,477	$ 367,830
Minimum amount of common equity tier I for adequacy purposes, ratio	7.00%	7.00%
Tier I Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 277,710	$ 261,358
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	0.0400	0.0400

Minimum amount of common equity tier I for adequacy purposes, ratio.

No definition available.

Name:	pgc_TierOneRiskBasedCommonEquityRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	pgc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum common equity tier I required to be well-capitalized, ratio.

+ References

No definition available.

+ Details

Name:	pgc_TierOneRiskBasedCommonEquityRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	pgc_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of total capital as defined by regulatory framework.

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

+ Details

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

- Definition

Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum total risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_CapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework.

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Ratio of Common Equity Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_CommonEquityTierOneCapitalRatio
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum Common Equity Tier 1 risk-based capital required for capital adequacy as defined by regulatory framework.

+ References

+ Details

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

- Definition

Amount of minimum Common Equity Tier 1 risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

Amount of Tier 1 leverage capital as defined by regulatory framework.

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of minimum Tier 1 leverage capital required for capital adequacy as defined by regulatory framework.

+ References

+ Details

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

- Definition

Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum Tier 1 leverage capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio of Tier 1 capital to average assets as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of Tier 1 risk-based capital as defined by regulatory framework.

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of minimum Tier 1 risk-based capital required for capital adequacy as defined by regulatory framework.

+ References

+ Details

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

- Definition

Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum Tier 1 risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio of Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	srt_ConsolidatedEntitiesAxis=srt_SubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RiskWeightedAssetsCalculationMethodologyAxis=pgc_ConservationBufferMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=srt_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: