Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2019

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

Summary of activity for Corporation's stock options

A summary of activity for the Corporation's stock options as of and for the three months ended March 31, 2019 is presented below:

	Non-Vested Stock Options Outstanding						Stock Options Outstanding
	Number of Options		Weighted- Average Exercise Price Per Share		Weighted- Average Grant Date Fair Value Per Share		Number of Options		Weighted- Average Exercise Price Per Share
Outstanding at December 31, 2018	221,658		$	38.37	$	7.16	777,443		$	31.42
Exercised	—		—		—		(89,443	)	29.77
Vested	(65,104	)	37.24		6.98		—		—
Forfeited/expired	(22,481	)	37.37		7.00		(27,095	)	36.89
Outstanding at March 31, 2019	134,073		$	39.08	$	7.28	660,905		$	31.42
Exercisable/vested at March 31, 2019							526,832		$	29.47

Summary of activity for restricted stock units and awards

A summary of the activity for RSUs as of and for the three months ended March 31, 2019 is presented below:

	Number of Units		Weighted-average grant date fair value per unit
Outstanding at December 31, 2018	576,490		$	49.35
Granted	368,197		45.03
Converted into shares of common stock	(118,481	)	38.27
Forfeited/expired	(12,832	)	50.35
Outstanding at March 31, 2019	813,374		$	48.99

The following table provides information regarding restricted stock awards. All restricted stock awards fully vested during the three months ended March 31, 2019.

Nonvested restricted stock awards	Number of Awards		Weighted-average acquisition-date fair value
Nonvested at January 1, 2019	40,852		$	46.23
Vested	(40,852	)	46.23
Nonvested at March 31, 2019	—		$	—