Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Components of share-based compensation awards

The following table summarizes the components of the Corporation's share-based compensation awards recorded as expense and the income tax benefit of such awards.

	Three Months Ended March 31,
	2018			2017
Stock and ESPP Options
Pre-tax compensation expense	$	24		$	48
Income tax benefit	(59		)	(246		)
Stock and ESPP option expense, net of income taxes	$	(35	)	$	(198	)
Restricted Stock Awards
Pre-tax compensation expense	$	851		$	525
Income tax benefit	(566		)	(710		)
Restricted stock awards expense, net of income taxes	$	285		$	(185	)
Total Share-Based Compensation
Pre-tax compensation expense	$	875		$	573
Income tax benefit	(625		)	(956		)
Total share-based compensation expense, net of income taxes	$	250		$	(383	)

Stock option activity under stock option plans

Stock option activity under the Corporation's stock option plans as of March 31, 2018 and changes during the three months ended March 31, 2018, were as follows:

	Number of Shares		Weighted-Average Exercise Price		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value
Outstanding at January 1, 2018	152,652		$	16.71
Exercised	(23,557	)	$	22.71
Cancelled	(200	)	$	28.25
Outstanding March 31, 2018	128,895		$	15.59	2.45	$	3,365,525
Vested and Expected to Vest at March 31, 2018	128,895		$	15.59	2.45	$	3,365,525
Exercisable at March 31, 2018	128,895		$	15.59	2.45	$	3,365,525

Unvested RSAs outstanding

The following table summarizes information on unvested RSAs outstanding as of March 31, 2018:

	Number of Shares		Weighted-Average Grant Date Fair Value
Unvested RSAs at January 1, 2018	366,993		$	29.79
Granted	4,687		$	42.11
Vested	(93,076	)	$	22.91
Forfeited	(140	)	$	22.87
Unvested RSAs at March 31, 2018	278,464		$	32.31