Fair Value Measurements and Fair Value of Financial Instruments (Details) - Schedule of Fair Value on a non-recurring basis - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Impaired Loans [Member] \| Commercial Real Estate [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Fair Value	$ 1,094	$ 1,099
Valuation Technique	Appraisals of collateral value	Appraisals of collateral value
Unobservable Inputs	Comparable sales	Comparable sales
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Appraisals Of Collateral Valuation Technique [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Capitalization rate	5.00%	6.00%
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Appraisals Of Collateral Valuation Technique [Member] \| Minimum [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Capitalization rate	0.00%	0.00%
Impaired Loans [Member] \| Commercial Real Estate [Member] \| Appraisals Of Collateral Valuation Technique [Member] \| Maximum [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Capitalization rate	10.00%	15.00%
Loans held-for-sale [Member] \| Market approach [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Valuation Technique		Market approach (70%)
Unobservable Inputs		Indications under securitized transactions expressed as a price to unpaid principal balance
Loans held-for-sale [Member] \| Commercial Real Estate [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Fair Value		$ 7,712
Loans held-for-sale [Member] \| Commercial taxi medallion loans [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Fair Value		$ 65,596
Valuation Technique		Discounted cash flows (30%)
Purchase amount per medallion		$ 59
Discounted Rate		14.00%
Loans held-for-sale [Member] \| Commercial taxi medallion loans [Member] \| Minimum [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Purchase amount per medallion		$ 40
Loans held-for-sale [Member] \| Commercial taxi medallion loans [Member] \| Maximum [Member]
Fair Value Measurements and Fair Value of Financial Instruments (Details) - Fair value, assets and liabilities measured on nonrecurring basis, valuation techniques [Line Items]
Purchase amount per medallion		$ 100

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No definition available.

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Capitalization rate.

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Purchase amount per medallion.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Description of significant assumptions used by management to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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Description of the inputs and valuation technique(s) used to measure fair value.

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