Stock Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2011

Stock Compensation Plans [Abstract]

Stock Compensation

	2011		2010		2009
Stock-based compensation expense	$	5,756	$	4,916	$	2,906
Income tax benefits		2,014		1,720		1,017

Stock Options Activity

	2011			2010			2009
Number of shares under stock options:
Options outstanding at beginning of year		201,674			523,973			748,673
Options granted		—			—			—
Options exercised		(107,575	)		(101,649	)		(200,225	)
Options canceled		(1,600	)		(220,650	)		(24,475	)
Options outstanding and exercisable at end of year		92,499			201,674			523,973
Weighted average exercise price:
Options exercised	$	12.25		$	11.51		$	13.83
Options canceled	$	11.80		$	22.60		$	22.69
Options outstanding and exercisable at end of year	$	10.69		$	11.53		$	16.30
Cash received from options exercised (in thousands)	$	1,318		$	2,179		$	2,770
Intrinsic value of options exercised (in thousands)	$	1,279		$	1,006		$	1,180
Intrinsic value of options outstanding (in thousands)	$	1,393		$	2,217		$	2,774

Options Outstanding And Exercisable

Exercise Prices	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Life (in years)
$10.17		80,499	$	10.17		0.85
$12.41		6,000		12.41		1.35
$15.88		6,000		15.88		0.36
Total		92,499	$	10.69		0.85

Restricted Stock Activity

	2011			2010			2009
Unvested shares at beginning of year		84,134			71,904			55,939
Shares granted		50,618			43,800			44,400
Shares cancelled		(431	)		—			(10,000	)
Shares vested		(40,839	)		(31,570	)		(18,435	)
Unvested shares at end of year		93,482			84,134			71,904
Weighted average fair value at grant date	$	23.06		$	19.80		$	18.18
Unrecognized compensation expense at end of year (in thousands)	$	932		$	735		$	668
Intrinsic value, unvested shares at end of year (in thousands)	$	2,407		$	1,895		$	1,552
Intrinsic value, shares vested during the year (in thousands)	$	934		$	682		$	345

Estimated Fair Value Of Performance Shares Granted

	2011			2010			2009
Risk-free interest rate		1.2	%		1.4	%		1.3	%
Expected life, in years		3			3			3
Expected volatility		26.9	%		27.8	%		25.8	%
Dividend yield		4.7	%		4.6	%		3.6	%
Weighted average grant date fair value (per share)	$	20.79		$	15.30		$	17.22

Performance Share Activity

	2011			2010			2009
Opening balance of unvested performance shares		325,700			300,601			252,923
Performance shares granted		184,600			168,700			163,900
Performance shares canceled		(2,177	)		—			(43,758	)
Performance shares vested		(156,778	)		(143,601	)		(72,464	)
Ending balance of unvested performance shares		351,345			325,700			300,601
Intrinsic value of unvested performance shares (in thousands).	$	9,047		$	7,335		$	6,490
Unrecognized compensation expense (in thousands)	$	2,991		$	2,330		$	2,453

Impact Of The Market Condition On The Vested Performance Shares

	2011			2010		2009
Performance shares vested		156,778			143,601		72,464
Impact of market condition on shares vested		(15,678	)		21,540		(72,464	)
Shares of common stock earned		141,100			165,141		—
Intrinsic value of common stock earned (in thousands)	$	3,633		$	3,719	$	—

Common Stock Repurchased

	2011		2010		2009
Stock repurchased from Ecova employees	$	464	$	2,593	$	4,725