Share-Based Compensation Plans (Tables)

9 Months Ended

Sep. 30, 2012

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

Summary of activity for Corporation's stock options

	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, 2012	162,883		$	21.27	$	6.55	815,119		$	28.29
Granted	229,763		23.78		7.08		229,763		23.78
Exercised	—		—		—		(1,003	)	19.97
Vested	(76,103	)	21.55		6.63		—		—
Forfeited/expired	(1,778	)	21.48		6.62		(17,133	)	30.46
Outstanding at September 30, 2012	314,765		$	23.03	$	6.92	1,026,746		$	27.26
Exercisable/vested at September 30, 2012							711,981		$	29.12

Assumptions of Black-Scholes option pricing model

Expected dividend yield	3.60		%
Risk-free interest rate	1.18		%
Expected stock price volatility	44.4		%
Expected life of options – in years	6.11
Weighted average per share fair value	$	7.08

Summary of activity for restricted stock performance units

	Number of Units		Weighted- Average Grant Date Fair Value  Per Unit
Outstanding at January 1, 2012	130,512		$	20.90
Granted	69,772		22.20
Converted into shares of common stock	(35,101	)	23.28
Forfeited/expired	(8,428	)	23.05
Outstanding at September 30, 2012	156,755		$	20.83