Debt instrument interest rate period.

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- Definition

Long term debt prepayment fee.

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- Definition

Trust preferred securities issued number.

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Trust preferred securities par value.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- 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

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The number of derivative instruments of a particular group held by the entity.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash inflow from issuance of preferred stocks by a business trust or other special purpose entity, mainly established by a bank holding entity, to third party investors. The trust's assets are deeply subordinated debentures of the bank holding entity. Most trust preferred securities are subject to a mandatory redemption upon the repayment of the debentures.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Debt - Additional Information (Long Term Debt) (Detail)			1 Months Ended		9 Months Ended	12 Months Ended
Debt - Additional Information (Long Term Debt) (Detail)	Sep. 30, 2016 USD ($)	Aug. 03, 2015 USD ($)	May 31, 2007 USD ($) shares	Jun. 30, 2003 USD ($) shares	Sep. 30, 2017	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2016 USD ($) derivative	Oct. 31, 2015 USD ($)	May 31, 2014 USD ($)
Debt Instrument [Line Items]
Advances from the FHLB						$ 25,000,000.0	$ 165,800,000
Repayments of debt						114,900,000
Long-term debt prepayment fee						4,133,000	$ 0	$ 0
Cash Flow Hedging \| Interest Rate Swap
Debt Instrument [Line Items]
Debt instrument, face amount									$ 30,000,000.0
Number of derivatives \| derivative									2
Collateralized FHLB Advances
Debt Instrument [Line Items]
Long-term debt prepayment fee						$ 4,100,000
Collateralized FHLB Advances \| Weighted Average
Debt Instrument [Line Items]
Weighted average interest rate of advances						0.77%	2.24%
Subordinated Debenture Offering \| Fixed To Floating
Debt Instrument [Line Items]
Debt instrument, face amount	$ 75,000,000.0
Debt instrument, interest rate	5.125%
Debt issuance costs	$ 1,500,000
Subordinated Debenture Offering \| Fixed To Floating \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.97%				3.97%
Junior Subordinated Debt \| Lakeland Bancorp Capital Trust IV
Debt Instrument [Line Items]
Debt instrument, face amount			$ 20,600,000
Debt instrument, basis spread on variable rate			1.52%
Distribution rate on securities			6.61%
Distribution of securities years			5 years
Trust preferred securities, issued (in shares) \| shares			20,000
Trust preferred securities, face value			$ 1,000
Proceeds of trust preferred securities			$ 20,000,000.0
Debentures extinguished		$ 10,000,000.0
Gain on extinguishment of debt		$ 1,800,000
Junior Subordinated Debt \| Lakeland Bancorp Capital Trust IV \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			1.52%
Junior Subordinated Debt \| Lakeland Bancorp Capital II
Debt Instrument [Line Items]
Debt instrument, face amount				$ 20,600,000
Debt instrument, basis spread on variable rate				3.10%
Distribution rate on securities				5.71%
Distribution of securities years				5 years
Trust preferred securities, issued (in shares) \| shares				20,000
Trust preferred securities, face value				$ 1,000
Proceeds of trust preferred securities				$ 20,000,000.0
Junior Subordinated Debt \| Lakeland Bancorp Capital II \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				3.10%
Highlands Bancorp, Inc. \| Subordinated Debenture Offering \| Fixed Rate
Debt Instrument [Line Items]
Debt instrument, face amount										$ 7,500,000	$ 5,000,000.0
Debt instrument, interest rate										6.94%	8.00%