Deposits Deposits - Narrative (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Banking and Thrift [Abstract]
Deposits obtained through brokers	$ 63,800,000	$ 0

Domestic Deposit, Brokered Certificates Of Deposits

No definition available.

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