Commitments, Contingent Liabilities and Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Commitments, Contingent Liabilities and Financial Instruments with Off-Balance Sheet Risk (Textual) [Abstract]
Unfunded loan commitments	$ 1,619,022	$ 1,263,059
Letters of credit outstanding	$ 68,946	$ 44,086

Commitments Contingent Liabilities And Financial Instruments With Off Balance Sheet Risk (Textual) [Abstract]

No definition available.

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