Stockholders' Equity and Stock Plans (Tables)

12 Months Ended

Dec. 31, 2018

Schedule of Share-based Compensation, Stock Options, Activity

A summary of stock option activity for the years ended December 31, 2018 and 2017 is presented in the following table. The intrinsic value of options outstanding and exercisable is calculated as the number of in-the-money options times the difference between the market price of our stock as of each year-end period presented and the exercise prices of the in-the-money options.



	Number of Shares		Weighted Average Exercise Price		Aggregate Intrinsic Value (in thousands)		Weighted Average Grant-Date Fair Value		Weighted Average Remaining Contractual Term (in years)
Options outstanding at December 31, 2016	363,578		$	20.60	$	5,190			5.77
Granted ¹	201,328		19.89				$	16.31
Cancelled, expired or forfeited	(4,022	)	21.99
Exercised	(42,948	)	19.31		585
Options outstanding at December 31, 2017	517,936		20.42		7,075				5.34
Exercisable (vested) at December 31, 2017	384,344		17.85		6,212				4.42
Options outstanding at December 31, 2017	517,936		20.42		7,075				5.34
Granted	74,096		33.97				7.17
Cancelled, expired or forfeited	(9,140	)	28.25
Exercised	(157,192	)	13.93		3,462
Options outstanding at December 31, 2018	425,700		25.01		6,910				5.85
Exercisable (vested) at December 31, 2018	311,050		22.57		5,809				4.94

¹ Includes 140,290 replacement stock option awards issued in the Acquisition with a $13.60 weighted average exercise price and a $20.36 weighted average grant-date fair value. See Note 18, Acquisition.

Schedule of Unrecognized Compensation Cost, Nonvested Awards

The following table summarizes non-vested restricted stock awards and changes during the years ended December 31, 2018 and 2017.



	Number of Shares		Weighted Average Grant-Date Fair Value
Non-vested awards at December 31, 2016	79,398		$	24.08
Granted	32,460		34.80
Vested	(20,642	)	22.89
Non-vested awards at December 31, 2017	91,216		28.16
Granted	37,040		33.58
Vested	(28,812	)	26.06
Cancelled or forfeited	(12,056	)	27.32
Non-vested awards at December 31, 2018	87,388		31.26

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range

A summary of the options outstanding and exercisable by price range as of December 31, 2018 is presented in the following table:



	Stock Options Outstanding as of December 31, 2018				Stock Options Exercisable as of December 31, 2018
Range of Exercise Prices	Stock Options Outstanding	Remaining Contractual Life (in years)	Weighted Average Exercise Price		Stock Options Exercisable	Weighted Average Exercise Price
$0.00 - $10.00	4,604	3.1	$	8.96	4,604	$	8.96
$10.01 - $20.00	110,394	2.3	16.94		110,394	16.94
$20.01 - $30.00	179,828	6.0	23.73		151,808	23.63
$30.01 - $40.00	127,040	8.8	33.94		40,410	33.78
$40.01 - $50.00	3,834	9.5	40.70		3,834	40.70
	425,700				311,050

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

We determine the fair value of stock options at the grant date using the Black-Scholes pricing model that takes into account the stock price at the grant date, the exercise price, and the following assumptions (weighted-average shown).



	Years ended December 31,
	2018		2017
Risk-free interest rate	2.60	%	1.66	%
Expected dividend yield on common stock	1.76	%	1.70	%
Expected life in years	5.9		2.4
Expected price volatility	22.47	%	25.58	%

Summary of Cash Dividends Paid to Common Shareholders

Presented below is a summary of cash dividends paid in 2017 and 2018 to common shareholders, recorded as a reduction from retained earnings. On January 25, 2019, the Board of Directors declared a $0.19 per share cash dividend, paid February 15, 2019 to the shareholders of record at the close of business on February 8, 2019.



	Years ended December 31,
(in thousands except per share data)	2018		2017
Cash dividends to common stockholders	$	8,860	$	6,896
Cash dividends per common share	$	0.64	$	0.56