Regulatory Matters - Summary of Capital Ratios (Detail) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Company
Total capital (to risk-weighted assets)
Total capital (to risk-weighted assets)	$ 1,167,429	$ 903,415
Total capital (to risk-weighted assets), For capital adequacy purposes	886,420	654,978
Tier 1 capital (to risk-weighted assets)
Tier 1 capital (to risk-weighted assets)	948,970	695,634
Tier one risk based capital required for capital adequacy with buffer	717,578	530,220
Common equity Tier 1 capital (to risk-weighted assets)
Common equity Tier 1 capital (to risk-weighted assets)	904,532	665,634
Common equity Tier 1 capital (to risk-weighted assets)	590,946	436,652
Tier 1 capital (to average assets)
Tier 1 capital (to average assets)	948,970	695,634
Tier 1 capital (to average assets), For capital adequacy purposes	$ 414,485	$ 326,813
Risk Based Ratios [Abstract]
Total capital (to risk-weighted assets), ratio	0.1383	0.1448
Tier 1 capital (to risk-weighted assets), ratio	0.1124	0.1115
Common equity Tier 1 capital (to risk-weighted assets), ratio	0.1071	0.1067
Tier 1 capital (to average assets), ratio	0.0916	0.0851
Total capital (to risk-weighted assets), For capital adequacy purposes , ratio	0.1050	0.1050
Tier one risk based capital required for capital adequacy with buffer to risk weighted assets	8.50%	8.50%
Common equity Tier 1 capital (to risk-weighted assets), For capital adequacy purposes, ratio	7.00%	7.00%
Tier 1 capital (to average assets), For capital adequacy purposes, ratio	0.0400	0.0400
Lakeland
Total capital (to risk-weighted assets)
Total capital (to risk-weighted assets)	$ 1,109,089	$ 852,339
Total capital (to risk-weighted assets), For capital adequacy purposes	885,667	654,692
Total capital (to risk - weighted assets), To be well capitalized under prompt corrective action provisions	843,492	623,516
Tier 1 capital (to risk-weighted assets)
Tier 1 capital (to risk-weighted assets)	1,038,661	792,363
Tier one risk based capital required for capital adequacy with buffer	716,968	529,989
Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions	674,794	498,813
Common equity Tier 1 capital (to risk-weighted assets)
Common equity Tier 1 capital (to risk-weighted assets)	1,038,661	792,363
Common equity Tier 1 capital (to risk-weighted assets)	590,444	436,461
Common equity Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions	548,270	405,285
Tier 1 capital (to average assets)
Tier 1 capital (to average assets)	1,038,661	792,363
Tier 1 capital (to average assets), For capital adequacy purposes	414,212	326,734
Tier 1 capital (to average assets), To be well capitalized under prompt corrective action provisions	$ 517,765	$ 408,418
Risk Based Ratios [Abstract]
Total capital (to risk-weighted assets), ratio	0.1315	0.1367
Tier 1 capital (to risk-weighted assets), ratio	0.1231	0.1271
Common equity Tier 1 capital (to risk-weighted assets), ratio	0.1231	0.1271
Tier 1 capital (to average assets), ratio	0.1003	0.0970
Total capital (to risk-weighted assets), For capital adequacy purposes , ratio	0.1050	0.1050
Tier one risk based capital required for capital adequacy with buffer to risk weighted assets	8.50%	8.50%
Common equity Tier 1 capital (to risk-weighted assets), For capital adequacy purposes, ratio	7.00%	7.00%
Tier 1 capital (to average assets), For capital adequacy purposes, ratio	0.0400	0.0400
Total capital (to risk - weighted assets), To be well capitalized under prompt corrective action provisions, ratio	0.1000	0.1000
Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions, ratio	0.0800	0.0800
Common equity Tier 1 capital (to risk-weighted assets), To be well capitalized under prompt corrective action provisions, ratio	6.50%	6.50%
Tier 1 capital (to average assets), To be well capitalized under prompt corrective action provisions, ratio	0.0500	0.0500

Common Equity, Tier One Risk-Based Capital Ratio, Well Capitalized, Minimum

No definition available.

Name:	lbai_CommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum
Namespace Prefix:	lbai_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Common equity tier one risk based capital required to be well capitalized

+ References

No definition available.

+ Details

Name:	lbai_CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalized
Namespace Prefix:	lbai_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Common Equity Tier One Risk Based Capital Required for Capital Adequacy Ratio

+ References

No definition available.

+ Details

Name:	lbai_CommonEquityTierOneRiskBasedCapitalRequiredforCapitalAdequacyRatio
Namespace Prefix:	lbai_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Common equity Tier 1 capital (to risk-weighted assets) [Abstract]

+ References

No definition available.

+ Details

Name:	lbai_CommonequityTier1capitaltoriskweightedassetsAbstract
Namespace Prefix:	lbai_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Tier One Risk Based Capital Required For Capital Adequacy With Buffer

+ References

No definition available.

+ Details

Name:	lbai_TierOneRiskBasedCapitalRequiredForCapitalAdequacyWithBuffer
Namespace Prefix:	lbai_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Tier One Risk Based Capital Required For Capital Adequacy With Buffer To Risk Weighted Assets

+ References

No definition available.

+ Details

Name:	lbai_TierOneRiskBasedCapitalRequiredForCapitalAdequacyWithBufferToRiskWeightedAssets
Namespace Prefix:	lbai_
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

+ 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

+ 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

- 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

- References

No definition available.

+ Details

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

- 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 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_AffiliatedEntityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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