Stock Plans (Tables)

12 Months Ended

Dec. 31, 2017

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

Schedule Of Stock-Based Compensation Expense

Stock-based compensation expense was as follows:

(In thousands)	2017		2016		2015
Restricted stock	$	4,691	$	3,456	$	3,035
Stock options	380		2,459		2,454
Performance stock	6,687		3,296		2,110
Total compensation expense before income taxes	11,758		9,211		7,599
Income tax benefit	4,440		3,375		2,896
Total compensation expense, net of income tax benefit	$	7,318	$	5,836	$	4,703

Schedule Of Fair Value Weighted Average Assumptions For Options Granted

Stock option expense is based on the fair value of stock option grants estimated on the grant dates using the Black-Scholes option pricing model and the following weighted average assumptions for options granted in 2016 and 2015. There were no stock options granted in 2017.

	2016			2015
Fair value per option	$	11.69		$	15.63
Risk-free interest rate	1.6		%	1.8		%
Expected dividend yield	2.8		%	2.3		%
Expected volatility	34		%	39		%
Expected life (years)	7.0			6.7

Summary Of Option Activity

A summary of option activity follows:

	Shares		Weighted Average Exercise Price		Exercisable at Year-end
Outstanding January 1, 2015	1,618,561		$	35.74
Granted	170,683		48.64
Exercised	(64,752	)	38.59
Expired	(1,109	)	44.36
Forfeited	(28,708	)	49.71
Outstanding December 31, 2015	1,694,675		36.69		1,280,665
Granted	235,233		44.50
Exercised	(341,063	)	37.34
Forfeited	(12,753	)	46.11
Outstanding December 31, 2016	1,576,092		37.63		1,098,615
Exercised	(620,646	)	29.75
Outstanding December 31, 2017	955,446		$	42.75	614,414

Characteristics of Outstanding and Exercisable Stock Options

For various exercise price ranges, characteristics of outstanding and exercisable stock options at December 31, 2017 were as follows:

	Stock Options Outstanding
Range of Exercise Prices	Shares	Weighted-Average
		Exercise Price		Remaining Life
$17.83 – $33.00	85,607	$	23.98	1.82
$33.01 – $45.00	464,364	40.23		5.59
$45.01 – $51.69	405,475	49.61		5.96
$17.83 – $51.69	955,446	$	42.75	5.41

	Stock Options Exercisable
Range of Exercise Prices	Shares	Weighted-Average
		Exercise Price		Remaining Life
$17.83 – $33.00	85,607	$	23.98	1.82
$33.01 – $45.00	260,278	36.88		3.57
$45.01 – $51.69	268,529	50.10		5.34
$17.83 – $51.69	614,414	$	40.86	4.10

Summary of Restricted Stock and Unit Activity

A summary of restricted stock and unit activity follows:

	Shares		Weighted Average Grant Date Fair Value
Unvested at January 1, 2015	268,743		$	45.34
Granted	83,725		48.06
Vested	(111,834	)	39.01
Forfeited	(22,925	)	45.84
Unvested at December 31, 2015	217,709		49.70
Granted	107,465		50.65
Vested	(76,568	)	49.12
Forfeited	(14,014	)	48.23
Unvested at December 31, 2016	234,592		49.76
Granted	72,878		75.27
Vested	(76,834	)	52.74
Forfeited	(3,475	)	50.46
Unvested at December 31, 2017	227,161		$	57.50

Summary of Performance Stock Unit Activity

A summary of performance stock unit activity follows:

	Shares		Weighted Average Grant Date Fair Value
Unvested at January 1, 2015	143,961		$	52.42
Granted	87,256		41.99
Vested	(52,839	)	41.75
Performance adjustments	3,086		41.45
Forfeited	(9,820	)	51.51
Unvested at December 31, 2015	171,644		50.24
Granted	65,355		44.28
Vested	(31,093	)	58.54
Performance adjustments	(15,682	)	58.54
Forfeited	(3,603	)	44.47
Unvested at December 31, 2016	186,621		46.18
Granted	98,886		72.73
Vested	(72,504	)	57.19
Performance adjustments	29,183		57.27
Unvested at December 31, 2017	242,186		$	55.06