Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

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

Schedule of unvested restricted stock awards

The following tables summarize the unvested restricted stock awards at June 30, 2017 and 2016.

	Six Months Ended June 30,
	2017					2016
Perfomance Awards	Shares			Weighted- Average Grant Date Fair Value		Shares			Weighted- Average Grant Date Fair Value
Unvested at beginning		33,226		$	42.60		—		$	—
Issued		36,523			57.49		34,957			42.60
Forfeited		(3,097	)		42.60		(1,731	)		42.60
Vested		(4,314	)		54.92		—			—
Unvested at end		62,338		$	50.45		33,226		$	42.60

	Six Months Ended June 30,
	2017					2016
Time Vested Awards	Shares			Weighted- Average Grant Date Fair Value		Shares			Weighted- Average Grant Date Fair Value
Unvested at beginning		262,966		$	33.60		369,093		$	24.43
Issued		91,097			62.70		104,775			46.39
Forfeited		(1,366	)		47.56		(7,744	)		40.12
Vested		(187,600	)		30.07		(195,738	)		22.53
Unvested at end		165,097		$	53.56		270,386		$	33.87

Schedule of activity of stock options

Below is a summary of stock option activity for the six months ended June 30, 2017 and 2016. The information excludes restricted stock units and awards.

	Six Months Ended June 30,
	2017					2016
	Shares			Weighted- Average Exercise Price		Shares			Weighted-Average Exercise Price
Beginning balance		216,859		$	8.80		298,740		$	9.97
Issued		—			—		1,500			49.91
Exercised		(64,090	)		7.47		(22,669	)		12.82
Forfeited		—			—		(1,100	)		15.48
Expired		—			—		(6,037	)		13.57
Ending balance		152,769		$	9.36		270,434		$	9.85

Schedule of stock option by exercise price range

The following summarizes information about stock options outstanding at June 30, 2017. The information excludes restricted stock units and awards.

Outstanding: Range of Exercise Prices				Stock Options Outstanding	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life
$	5.76	$	10.72	101,405	$	5.76		1.53
$	10.73	$	11.40	41,389		10.84		1.02
$	11.41	$	24.86	3,225		22.79		6.27
$	24.87	$	49.91	6,750		47.83		8.62
				152,769	$	9.36		1.80

Exercisable: Range of Exercise Prices				Stock Options Exercisable	Weighted-Average Exercise Price
$	5.76	$	10.72	66,707	$	5.76
$	10.73	$	11.40	41,389		10.84
$	11.41	$	24.86	1,565		22.64
$	24.87	$	49.91	375		49.91
				110,036	$	8.06

Schedule of valuation assumptions used for stock options

The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option pricing model with the assumptions as shown in the table below used for grants during the years ended December 31, 2016 and 2015. There were no grants of stock options during the six months ended June 30, 2017.

	Six Months Ended June 30, 2017		Years Ended December 31,
			2016			2015
Expected volatility		n/a		24.23	%		31.21	%
Weighted-Average volatility		n/a		24.23	%		31.21	%
Expected dividends		—		—			—
Expected term (in years)		n/a		7.0			7.0
Risk-free rate		n/a		1.37	%		1.64	%
Weighted-average fair value (grant date)		n/a	$	14.27		$	16.73