Acquisitions - Pro Forma Result of Comparable Prior Reporting Period (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) $ / shares
Business Acquisition, Pro Forma Information [Abstract]
Net Interest Income	$ 30,126
Provision for Loan Losses	(247)
Net Interest Income after Provision for Loan Losses	30,373
Non-interest Income	7,903
Non-interest Expense	24,684
Income before Income Taxes	13,592
Income Tax Expense	3,863
Net Income	9,729
Net Income Available to Common Shareholders	$ 9,729
Basic Earnings per Share | $ / shares	$ 0.44
Diluted Earnings per Share | $ / shares	$ 0.44