The period of deferral of principle and interest terms due to national emergency.

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The percentage of allowance for credit loss on total non performing loans.

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The percentage of allowance for credit loss on total financial receivables.

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The maximum amount of funds approved to provide funds under payback protection program (PPP).

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No definition available.

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Number of business units.

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Number of TDR loans transferred to non-performing loans during the period.

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No definition available.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Number of financing receivables that have been modified by troubled debt restructurings.

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

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Amount of financing receivable on nonaccrual status.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) item	Mar. 31, 2019 USD ($) item	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of business units \| item	3
Allowance for credit losses	$ 28,098	$ 21,015	$ 21,751	$ 20,945
Percentage of financing receivable on total loans	0.47%
Percentage of financing receivable on gross loans	167.73%
Payback protection program , maximum fund	$ 64,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Modifications, Number of Contracts \| item	0	0
Financing Receivable, Nonaccrual			$ 12,813
Minimum [Member]
Term of Deferral interest and principal payments	1 year
Maximum [Member]
Term of Deferral interest and principal payments	6 months
Interest and dividends receivable
Interest Receivable	$ 23,000
Payment Deferral
Aggregate outstanding loans	839,000
Extension Of Credit [Member]
Commitments and contingencies (Note 15)	51,900
Extension Of Lines Of Credit [Member]
Commitments and contingencies (Note 15)	$ 259,900
Performing Financial Instruments [Member]
Financing Receivable, Modifications, Number of Contracts	23		24
Commercial Real Estate Portfolio Segment [Member]
Allowance for credit losses	$ 6,791	$ 4,278	$ 4,429	4,315
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral
Aggregate outstanding loans	673,000
Multi-family Residential Portfolio Segment [Member]
Allowance for credit losses	$ 5,895	5,493	$ 5,391	5,676
Taxi Medallion Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Modifications, Number of Contracts	6		7
Financing Receivable, Nonaccrual	$ 1,500		$ 1,700
Commercial Business and Other Portfolio Segment [Member]
Allowance for credit losses	$ 10,637	$ 7,962	8,554	$ 7,591
TDR Loans Transferred to Non-performing, Number of Contracts \| item	1
Commercial Business and Other Portfolio Segment [Member] \| Payment Deferral
Aggregate outstanding loans	$ 166,000
Commercial Business and Other Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Nonaccrual	1,000		$ 900
Overdrafts [Member]
Allowance for credit losses	$ 7,100