Accounting Policies - Summary of Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Basic earnings per share
Net Income	$ 8,224	$ 5,381
Less: Preferred stock dividends		42
Net Income Available to Common Shareholders	$ 8,224	$ 5,339
Weighted average common shares outstanding	22,175,526	17,924,124
Basic Earnings Per Share	$ 0.37	$ 0.30
Diluted earnings per share
Net income available to common shareholders	$ 8,224	$ 5,339
Effect of dilutive securities:
Weighted average shares outstanding	22,326,071	18,012,726
Diluted Earnings Per Share	$ 0.37	$ 0.30
Restricted Stock [Member]
Effect of dilutive securities:
Effect of dilutive securities	36,336	31,550
Stock Options [Member]
Effect of dilutive securities:
Effect of dilutive securities	114,209	57,053

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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