Stock Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2014

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

Stock Compensation

	2014		2013		2012
Stock-based compensation expense	$	6,007	$	5,037	$	4,549
Income tax benefits	2,102		1,763		1,592

Stock Options Activity

	2013			2012
Number of shares under stock options:
Options outstanding at beginning of year	3,000			92,499
Options granted	—			—
Options exercised	(3,000		)	(89,499		)
Options canceled	—			—
Options outstanding and exercisable at end of year	—			3,000
Weighted average exercise price:
Options exercised	$	12.41		$	10.63
Options canceled	$	—		$	—
Options outstanding and exercisable at end of year	$	—		$	12.41
Cash received from options exercised (in thousands)	$	37		$	951
Intrinsic value of options exercised (in thousands)	$	40		$	1,349
Intrinsic value of options outstanding (in thousands)	$	—		$	35

Restricted Stock Activity

	2014			2013			2012
Unvested shares at beginning of year	104,416			117,118			93,482
Shares granted	62,075			44,556			70,281
Shares canceled	(1,550		)	(1,802		)	(790		)
Shares vested	(52,899		)	(55,456		)	(45,855		)
Unvested shares at end of year	112,042			104,416			117,118
Weighted average fair value at grant date	$	28.37		$	26.04		$	25.83
Unrecognized compensation expense at end of year (in thousands)	$	1,349		$	1,199		$	1,428
Intrinsic value, unvested shares at end of year (in thousands)	$	3,961		$	2,943		$	2,824
Intrinsic value, shares vested during the year (in thousands)	$	1,473		$	1,363		$	1,173

Estimated Fair Value of Performance Shares Granted

	2014			2013			2012
TSR assumptions
Risk-free interest rate	0.7		%	0.4		%	0.3		%
Expected life, in years	3			3			3
Expected volatility	17.9		%	19.1		%	22.7		%
Dividend yield	4.5		%	4.6		%	4.5		%
Weighted average grant date fair value (per share)	$	24.64		$	23.30		$	26.06
CEPS assumptions
Weighted average share price on date of grant	$	28.09		$	—		$	—
Annual dividends per share	1.22			—			—
Risk-free interest rate	0.7		%	—		%	—		%
Weighted average grant date fair value of equity component (per share)	$	24.48		$	—		$	—

Performance Share Activity

	2014			2013			2012
TSR Awards
Opening balance of unvested TSR shares	344,684			359,700			351,345
TSR shares granted	117,550			175,000			181,000
TSR shares canceled	(6,816		)	(13,298		)	(4,544		)
TSR shares vested	(167,584		)	(176,718		)	(168,101		)
Ending balance of unvested TSR shares	287,834			344,684			359,700
Intrinsic value of unvested performance shares (in thousands)	$	10,175		$	9,717		$	8,672
Unrecognized compensation expense (in thousands)	$	2,833		$	3,651		$	3,800
CEPS Awards
Opening balance of unvested CEPS shares	—			—			—
CEPS shares granted	59,025			—			—
CEPS shares canceled	(1,008		)	—			—
CEPS shares vested	—			—			—
Ending balance of unvested CEPS shares	58,017			—			—
Intrinsic value of unvested performance shares (in thousands)	$	2,051		$	—		$	—
Unrecognized compensation expense (in thousands)	$	1,577		$	—		$	—

Impact of the Market Condition on the Vested Performance Shares

	2014			2013			2012
TSR shares vested based on service condition	167,584			176,718			168,101
Impact of market condition on shares vested	(70,385		)	(176,718		)	(168,101		)
Shares of common stock earned	97,199			—			—
Intrinsic value of common stock earned (in thousands)	$	3,436		$	—		$	—