Accounting for Stock Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

The following table summarizes stock option activity during the three year period ended December 31, 2014:

Options	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at December 31, 2011		2,163,825		$	8.12
Granted		160,000			12.88
Exercised		(176,896	)		4.46
Forfeited		(17,000	)		4.05
Outstanding at December 31, 2012		2,129,929		$	8.82		6.99	$	5,640
Granted		510,000			19.64
Exercised		(672,753	)		7.21
Forfeited		(24,000	)		11.27
Outstanding at December 31, 2013		1,943,176		$	12.19		5.31	$	28,379
Granted		605,000			30.15
Exercised		(731,142	)		9.84
Forfeited		(132,500	)		19.30
Outstanding at December 31, 2014		1,684,534			19.11		5.10	$	30,111
Exercisable at December 31, 2012		1,520,720		$	7.57		6.20	$	5,966
Exercisable at December 31, 2013		1,055,176		$	12.21		4.58	$	19,314
Exercisable at December 31, 2014		632,034		$	10.13		3.97	$	16,744

Fair Value of Option on Date of Grant

The fair value of each option is estimated on the date of grant using the Black-Scholes option-pricing model. This model incorporates certain assumptions for inputs including a risk-free interest rate, expected dividend yield of the underlying common stock, expected option life and expected volatility in the market value of the underlying common stock. The following assumptions were used for options issued in the following periods:

	2014	2013	2012
Expected volatility	37%	34%	47%
Weighted average expected volatility	37%	34%	47%
Expected lives	3 yrs.	3 yrs.	3 yrs.
Risk-free interest rate	0.60-1.00%	0.57-0.65%	0.43%
Expected dividend yield	none	none	none

Restricted Stock Activity

The following table summarizes restricted stock activity during the three year period ended December 31, 2014:

Unvested Restricted Shares	Shares			Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2011		24,900		$	16.69
Granted		155,280			12.94
Vested		(17,922	)		15.54
Forfeited		—			—
Outstanding at December 31, 2012		162,258		$	13.23
Granted		183,967			18.78
Vested		(102,258	)		13.59
Forfeited		—			—
Outstanding at December 31, 2013		243,967		$	17.43
Granted		104,584			27.79
Vested		(129,092	)		16.45
Forfeited		(42,375	)		19.77
Outstanding at December 31, 2014		177,084		$	23.70

SARs Activity

The following table summarizes SARs activity during the three year period ended December 31, 2014:

Stock Appreciation Rights	Units			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at December 31, 2012		—		$	—
Granted		495,000			19.19
Exercised		—			—
Forfeited		—			—
Outstanding at December 31, 2013		495,000		$	19.19		6.5	$	3,770
Granted		754,000			34.70
Exercised		(68,750	)		19.10
Forfeited		(120,000	)		21.46
Outstanding at December 31, 2014		1,060,250			29.97		6.11	$	9,991
Exercisable at December 31, 2013		—		$	—		—		—
Exercisable at December 31, 2014		35,000		$	19.43		5.53	$	602