Stock Option Plans (Tables)

6 Months Ended

Jun. 30, 2017

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

The following table summarizes the amount and activity of each grant with outstanding unexercised options, the total value and variables used in the computation and the amount expensed and included in general and administrative expense in the Consolidated Statements of Operations for the six months ended June 30, 2017.



	Directors
Grant date	4/25/2008			4/24/2009			5/7/2010			5/13/2011			5/4/2012			5/10/2013			5/9/2014			5/8/2015			5/6/2016			5/5/2017			Subtotals
Total grant	30,000			32,500			32,500			32,500			35,000			35,000			30,000			35,000			32,500			27,500			322,500
Vested	30,000			32,500			32,500			32,500			35,000			35,000			30,000			35,000			32,500			27,500			322,500
Exercised	20,000			27,500			25,000			22,500			22,500			20,000			15,000			10,000			5,000			—			167,500
Forfeited	7,500			—			2,500			2,500			—			—			—			—			—			—			12,500
Exercisable at June 30, 2017	2,500			5,000			5,000			7,500			12,500			15,000			15,000			25,000			27,500			27,500			142,500
Remaining unexercised	2,500			5,000			5,000			7,500			12,500			15,000			15,000			25,000			27,500			27,500			142,500
Exercise price	$	50.15		$	32.68		$	38.76		$	41.82		$	39.29		$	44.42		$	47.03		$	51.07		$	57.74		$	59.41
Volatility	0.237			0.344			0.369			0.358			0.348			0.333			0.173			0.166			0.166			0.173
Expected life (years)	7.0			6.0			5.0			5.0			5.0			5.0			5.0			5.0			5.0			5.0
Assumed yield	4.09		%	4.54		%	4.23		%	4.16		%	4.61		%	4.53		%	4.48		%	4.54		%	3.75		%	3.45		%
Risk-free rate	3.49		%	2.19		%	2.17		%	1.86		%	0.78		%	0.82		%	1.63		%	1.50		%	1.23		%	1.89		%
Total value at grant date	$	254,700		$	222,950		$	287,950		$	297,375		$	257,250		$	278,250		$	109,500		$	125,300		$	151,125		$	165,550		$	2,149,950
Expensed in previous years	254,700			222,950			287,950			297,375			257,250			278,250			109,500			125,300			151,125			—			1,984,400
Expensed in 2017	—			—			—			—			—			—			—			—			—			165,550			165,550
Future expense	—			—			—			—			—			—			—			—			—			—			—
	Officers
Grant date	5/13/2011			5/4/2012			5/10/2013			5/9/2014			5/8/2015			5/6/2016			5/5/2017			Subtotal									Grand Totals
Total grant	162,500			242,500			202,500			170,000			190,000			194,000			205,000			1,366,500									1,689,000
Vested	118,750			107,500			171,875			126,875			94,375			48,500			—			667,875									990,375
Exercised	96,100			91,830			76,750			31,875			6,875			—			—			303,430									470,930
Forfeited	43,750			135,000			30,625			1,875			3,125			1,875			—			216,250									228,750
Exercisable at June 30, 2017	22,650			15,670			95,125			95,000			87,500			48,500			—			364,445									506,945
Remaining unexercised	22,650			15,670			95,125			136,250			180,000			192,125			205,000			846,820									989,320
Exercise price	$	41.82		$	39.29		$	44.42		$	47.03		$	51.07		$	57.74		$	59.41
Volatility	0.330			0.315			0.304			0.306			0.298			0.185			0.170
Expected life (years)	8.0			8.0			8.0			7.0			7.0			7.0			7.0
Assumed yield	4.81		%	5.28		%	5.12		%	4.89		%	4.94		%	3.80		%	3.50		%
Risk-free rate	2.75		%	1.49		%	1.49		%	2.17		%	1.89		%	1.55		%	2.17		%
Gross value at grant date	$	1,366,625		$	1,518,050		$	1,401,300		$	1,349,800		$	1,584,600		$	1,136,840		$	1,324,300		$	9,681,515								$	11,831,465
Estimated forfeitures	367,937			845,100			211,925			168,749			141,780			86,628			91,642			1,913,761									1,913,761
Expensed in previous years	998,688			672,950			1,031,134			787,392			601,180			175,032			—			4,266,376									6,250,776
Expensed in 2017	—			—			158,241			147,636			180,354			131,274			51,360			668,865									834,415
Future expense	—			—			—			246,023			661,286			743,906			1,181,298			2,832,513									2,832,513
Weighted average term of remaining future expense (in years)				2.8

Summary of Option Activity

The table below summarizes the option activity for the six months ended June 30, 2017:



	Number of Shares		Weighted Average Exercise Price per share		Aggregate Intrinsic Value
Outstanding at January 1	833,630		$	49.92	$	13,913,891
Granted	232,500		59.41		—
Exercised	(73,060	)	46.63		1,121,042
Expired/Forfeited	(3,750	)	53.73
Outstanding at June 30	989,320		52.38		5,874,639
Exercisable at June 30	506,945		48.69		4,749,306