Securities - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Recognized losses on equity securities	$ 26,000
Securities pledged or sold under agreements to repurchase	1,200,000,000	$ 1,300,000,000
Equity method investments	1,400,000	$ 1,700,000
Equity method investment, other than temporary Impairment	0
Federal Home Loan Bank New York (FHLBNY)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank, advances, branch of FHLB bank, amount of advances	37,400,000
Federal Home Loan Bank Pittsburgh (FHLBPITT)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank, advances, branch of FHLB bank, amount of advances	14,800,000
Atlantic Central Bankers Bank (ACBB)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank, advances, branch of FHLB bank, amount of advances	$ 95,000

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

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