Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2013

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, 2013 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 January 1, 2013	314,765		$	23.03	$	6.92	997,222		$	27.24
Granted	244,219		25.14		7.40		244,219		25.14
Exercised	—		—		—		(5,216	)	21.70
Vested	(95,575	)	23.93		7.19		—		—
Forfeited/expired	(12,311	)	23.43		7.00		(12,311	)	23.43
Outstanding at March 31, 2013	451,098		$	23.97	$	7.12	1,223,914		$	26.89
Exercisable/vested at March 31, 2013							772,816		$	28.59

Assumptions of Black-Scholes option pricing model

The fair value of the stock options granted during the three months ended March 31, 2013 was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions.

Expected dividend yield	3.50		%
Risk-free interest rate	1.34		%
Expected stock price volatility	42.1		%
Expected life of options – in years	7.0
Weighted average per share fair value	$	7.40

Summary of activity for restricted stock performance units

A summary of the activity for restricted stock units as of and for the three months ended March 31, 2013 is presented below:

	Number of Units		Weighted- Average Grant Date Fair Value  Per Unit
Outstanding at January 1, 2013	156,510		$	20.83
Granted	71,429		23.41
Converted into shares of common stock	(35,303	)	22.48
Forfeited/expired	(1,754	)	25.97
Outstanding at March 31, 2013	190,882		$	21.44