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 outstanding balance of financing receivable that are in active forbearance.

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The number of financing receivables in active forbearances.

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

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Number of business units.

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Percentage of financing receivable in active forbearance.

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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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Loans and Allowance for Loan Losses (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Jun. 30, 2020 USD ($) item contract loan	Jun. 30, 2019 USD ($) loan	Dec. 31, 2019 USD ($) contract	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of business units \| item			3
Allowance for credit losses	$ 36,710	$ 21,510	$ 36,710	$ 21,510	$ 21,751	$ 28,098	$ 21,015	$ 20,945
Percentage of financing receivable on total loans			0.61%
Percentage of financing receivable on gross loans			181.85%
Payback protection program , maximum fund	$ 93,200		$ 93,200
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| loan	0	0	0	0
Financing Receivable, Modifications, Number of Contracts \| loan	0	0	0	0
Non-accrual loans					$ 12,813
Minimum [Member]
Term of Deferral interest and principal payments			1 month
Maximum [Member]
Term of Deferral interest and principal payments			6 months
Interest and dividends receivable
Interest Receivable	$ 28,200		$ 28,200
Extension Of Credit [Member]
Commitments and contingencies (Note 15)	46,100		46,100
Extension Of Lines Of Credit [Member]
Commitments and contingencies (Note 15)	$ 301,300		$ 301,300
Performing Financial Instruments [Member]
Financing Receivable, Modifications, Number of Contracts \| contract			22		24
Loans Receivable [Member]
Number of active forbearances \| loan	808		808
Outstanding balance in active forbearance	$ 1,300,000		$ 1,300,000
Commercial Real Estate Portfolio Segment [Member]
Allowance for credit losses	$ 6,971	$ 4,265	$ 6,971	$ 4,265	$ 4,429	6,791	4,278	4,315
Commercial Real Estate Portfolio Segment [Member] \| Loans Receivable [Member]
Percentage of financing receivable in active forbearance	82.00%		82.00%
Multi-family Residential Portfolio Segment [Member]
Allowance for credit losses	$ 8,935	5,506	$ 8,935	5,506	$ 5,391	5,895	5,493	5,676
Taxi Medallion Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Financing Receivable, Modifications, Number of Contracts \| contract			6		7
Non-accrual loans	1,500		$ 1,500		$ 1,700
Commercial Business and Other Portfolio Segment [Member]
Allowance for credit losses	15,248	$ 8,444	15,248	$ 8,444	8,554	$ 10,637	$ 7,962	$ 7,591
Commercial Business and Other Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Non-accrual loans	1,000		1,000		$ 900
Overdrafts [Member]
Allowance for credit losses	$ 16,700		$ 16,700
Business Banking Portfolio Segment [Member] \| Loans Receivable [Member]
Percentage of financing receivable in active forbearance	18.00%		18.00%