Exercise price per share or per unit of warrants or rights outstanding.

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Stock Incentive Plans - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2018	Mar. 11, 2017	Apr. 06, 2013	Jun. 15, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards issued (in shares)	962,799	713,998	574,125
Common stock shares available under incentive compensation plans (in shares)	2,332,770
Unrecognized compensation expense	$ 14.0
Intrinsic value of outstanding and exercisable stock options	$ 0.9
Common shares available for purchase under warrants (in shares)							651,042
Annapolis Bancorp, Inc. (ANNB)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price (in usd per share)	$ 3.02
Warrant issued, shares (in shares)						342,564
Warrants converted to purchase common stock (in shares)				405,489
Yadkin Financial Corporation (YDKN)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price (in usd per share)	$ 9.33
Warrant issued, shares (in shares)					207,320
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards issued, years	3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards issued (in shares)	962,799	713,998	574,125
Unrecognized compensation expense	$ 13.6
Amount subject to accelerated vesting under Incentive Compensation Plan	$ 0.8
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for purchase under warrants (in shares)							1,302,083
Service- Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards issued, years	3 years
Unrecognized compensation expense	$ 9.0
Performance- Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 5.0
Performance- Based Units \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards issued (in shares)	283,037	251,379
Warrant Expires in 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price (in usd per share)	$ 11.52
Warrant Expires in 2019 \| Annapolis Bancorp, Inc. (ANNB)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price (in usd per share)						$ 3.57
Warrant Expires in 2019 \| Yadkin Financial Corporation (YDKN)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant issued, exercise price (in usd per share)					$ 9.63
Warrant issued, shares (in shares)	213,986				207,320