Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

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

Schedule of Stock-Based Compensation Expense

A summary of stock-based compensation expense and related tax benefits for the years ended December 31, 2017, 2016 and 2015 is as follows:

	Year Ended December 31,
	2017		2016		2015
	(in thousands)
Stock options	$	3,740	$	3,193	$	2,781
Restricted stock and restricted stock units	1,205		550		252
Employee Stock Purchase Plan	1,040		509		508
Total pre-tax stock-based compensation expense charged against income (1)	$	5,985	$	4,252	$	3,541
Total recognized tax benefit related to stock-based compensation	$	5,709	$	2,773	$	1,873

⁽¹⁾  Stock-based compensation expense is recorded in the selling, general and administrative caption in the Consolidated Statements of Comprehensive Income.

Summary of Stock Options Activity

A summary of stock options outstanding under the Plan as of December 31, 2017 and changes during 2017 is as follows:

	Number of Shares		Weighted Average Exercise Price
	(in thousands, except per share data)
December 31, 2016	2,615		$	24.61
Granted	544		$	39.38
Exercised	(682	)	$	18.95
Forfeited	(100	)	$	34.10
Expired	(3	)	$	23.49
December 31, 2017	2,374		$	29.22

Assumption for Fair Value of Options Granted

The fair value of the stock option awards granted during 2017, 2016 and 2015 were estimated on the dates of grant using the Black-Scholes option valuation model and the following assumptions:

	Year Ended December 31,
	2017		2016		2015
Risk-free interest rate	2.0	%	2.0	%	1.9	%
Weighted average expected life	5.8 years		5.8 years		5.8 years
Expected volatility	25.1	%	26.0	%	27.2	%
Dividend yield	1.9	%	2.0	%	2.2	%

Summarized Information of Stock Options Outstanding

The following table summarizes other information about the stock options at December 31, 2017:

	December 31, 2017
	(dollars in thousands, except per share data)
Outstanding:
Aggregate intrinsic value	$	55,789
Weighted average remaining contractual life	6.5 years
Exercisable:
Number of options	954
Weighted average exercise price	$	22.19
Aggregate intrinsic value	$	29,134
Weighted average remaining contractual life	4.7 years

Summary of Stock Options Outstanding

A summary of the outstanding restricted stock units as of December 31, 2017 and changes during 2017 is as follows:

	Number of Restricted Units	Weighted Average Grant Date Fair Value
	(in thousands, except per share data)
December 31, 2016	—	$	—
Granted	88	$	40.16
Vested	—	$	—
Forfeited	—	$	—
December 31, 2017	88	$	40.16

A summary of the restricted stock outstanding under the Plan as of December 31, 2017 and changes during 2017 are as follows:

	Number of Restricted Shares		Weighted Average Grant-Date Fair Value
	(in thousands, except per share data)
December 31, 2016	74		$	32.09
Granted	—		$	—
Vested	(17	)	$	31.41
Forfeited	—		$	—
December 31, 2017	57		$	32.30

Weighted Average Grant-Date Fair Values and Intrinsic Values of Options Vested

The weighted average grant-date fair values and total fair values of restricted stock vested during 2017, 2016 and 2015 are as follows:

	Year Ended December 31,
	2017		2016		2015
	(in thousands, except per share data)
Weighted average grant-date fair value of restricted stock granted	$	—	$	34.14	$	30.30
Total fair value of restricted stock vested	$	690	$	311	$	123

Summary of ESPP Annual Offerings

The following table summarizes information about the Company’s ESPP annual offerings for the years ended December 31, 2017, 2016 and 2015:

	Year Ended December 31,
	2017		2016		2015
	(in thousands, except per share data)
Common shares purchased	54		53		59
Per common share purchase price	$	33.29	$	29.64	$	26.29

Summary of Information Of SERP

The following table summarizes information about the SERP for the plan years ended December 31, 2017, 2016 and 2015:

	Year Ended December 31,
	2017		2016		2015
	(in thousands)
SERP expense (1)	$	503	$	511	$	538
Treasury shares issued to fund SERP expense (2)	9		13		15
SERP trust account balance at December 31 (3)	$	42,467	$	34,599	$	37,765
Unrealized gain (loss) recorded in SERP liability account	$	4,534	$	1,495	$	(62	)

⁽¹⁾  Both the SERP match and the deferrals are included in the selling, general and administrative caption in the Consolidated Statements of Comprehensive Income.

⁽²⁾  Shares related to the SERP match for each year are funded at the beginning of the subsequent year.

⁽³⁾  SERP trust account investments are recorded at their fair value which is based on quoted market prices. Differences between such amounts in the table above and the deferred compensation funding asset reported on the Consolidated Balance Sheets represent the value of Company Common Stock held in the Plan participants’ trust accounts and reported by the Company as treasury stock in the Consolidated Balance Sheets.