Stock Options and Restricted Stock (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock Options Outstanding

The following table summarizes information about the stock options outstanding under the 2005 Incentive Plan at December 31, 2015, 2016 and 2017:

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (in years)
Outstanding at January 1, 2015		282,083			11.30		3.6
Granted		—			—		—
Exercised		(193,204	)		9.55		—
Canceled, forfeited, or expired		—			—		—
Outstanding at December 31, 2015		88,879			12.10		4.3
Exercisable at December 31, 2015		88,879			12.10		4.3
Outstanding at January 1, 2016		88,879			12.10		4.3
Granted		—			—		—
Exercised		(68,879	)		12.14		3.3
Canceled, forfeited, or expired		—			—		—
Outstanding at December 31, 2016		20,000			8.71		3.1
Exercisable at December 31, 2016		20,000			8.71		3.1
Outstanding at January 1, 2017		20,000			8.71		3.1
Granted		—			—		—
Exercised		—			—		—
Canceled, forfeited, or expired		—			—		—
Outstanding at December 31, 2017		20,000			5.21		2.1
Exercisable at December 31, 2017		20,000			5.21		2.1

Weighted Average Grant Date Fair Values of Options Granted

	2017		2016		2015
	(in thousands)
Cash received from option exercises	$	—	$	837	$	1,844
Total tax benefits realized for tax deductions from    options exercised		—		833		2,109
Total intrinsic value of options exercised		—		2,967		6,969
Grant date fair value of options vested		—		—		—
Aggregate intrinsic value of vested options outstanding		1,128		1,073		3,448

Restricted Stock Outstanding

The following table summarizes information about the restricted stock outstanding under the 2005 Incentive Plan at December 31, 2017:

	Shares			Weighted- Average Grant- Date Fair Value per Share
Nonvested balance at January 1, 2015		2,400			27.35
Granted		—			—
Vested		(800	)		27.35
Forfeited		—			—
Nonvested balance at December 31, 2015		1,600			27.35
Granted		—			—
Vested		(800	)		27.35
Forfeited		—			—
Nonvested balance at December 31, 2016		800			27.35
Granted		—			—
Vested		(800	)		27.35
Forfeited		—			—
Nonvested balance at December 31, 2017		—			—

The following table summarizes information about the restricted stock outstanding under the 2012 Incentive Plan at December 31, 2017:

	Shares			Weighted- AverageGrant- Date Fair Value per Share
Nonvested balance at January 1, 2015		72,921			34.59
Granted		50,461			45.80
Vested		(27,537	)		37.27
Forfeited		(18,317	)		35.48
Nonvested balance at December 31, 2015		77,528			40.57
Granted		27,077			54.44
Vested		(26,294	)		45.18
Forfeited		(1,919	)		—
Nonvested balance at December 31, 2016		76,392			43.91
Granted		9,326			55.58
Vested		(24,839	)		43.89
Forfeited		—			—
Nonvested balance at December 31, 2017		60,879			45.71

The following table summarizes information about the restricted stock outstanding under the Non-Employee Director Restricted Stock Plan at December 31, 2017:

	Shares			Weighted- Average Grant- Date Fair Value per Share
Nonvested balance at January 1, 2015		5,229			37.27
Granted		7,112			44.26
Vested		(5,229	)		37.27
Forfeited		—			—
Nonvested balance at December 31, 2015		7,112			44.26
Granted		5,952			63.57
Vested		(7,488	)		44.54
Forfeited		—			—
Nonvested balance at December 31, 2016		5,576			64.50
Granted		6,454			54.20
Vested		(5,576	)		64.50
Forfeited		—			—
Nonvested balance at December 31, 2017		6,454			54.20