Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Interest-bearing deposits in other banks, collateral	$ 1,000	$ 3,380
Amortized cost of investment securities, available for sale	1,224,227	847,791
Investment securities, held-to-maturity-at cost, fair value	149,431	162,853
Allowance for loan losses	$ 39,539	$ 40,599
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	65,000,000	65,000,000
Common stock, issued (in shares)	56,926,978	56,279,527
Treasury stock (in shares)	25,552,887	24,861,145

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Interest-Bearing Deposits In Banks and Other Financial Institutions, Collateral

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