Stock-Based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2016

Dec. 31, 2015

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

Schedule of Share-based Compensation, Stock Options, Activity

A summary of option activity under the Omnibus Plan as of December 31, 2016 and changes during the year then ended is presented below:

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at beginning of year	1,203,035		$	80.58
Granted	384,306		57.15
Exercised	(142,969	)	55.58
Expired	(63,030	)	70.01
Forfeited	(23,844	)	77.71
Outstanding at end of year	1,357,498		$	77.12	2.9	$	6,027
Vested or expected to vest at end of year	1,352,575		$	77.17	2.9	$	5,977
Exercisable at end of year	648,248		$	84.47	2.0	$	1,339

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

The following weighted average assumptions were used to estimate the grant date fair value of options granted during the years ended December 31, 2016, 2015 and 2014 using the Black-Scholes option pricing model:

	2016		2015		2014
Expected volatility	37	%	27	%	22	%
Expected term (in years)	4		4		4
Risk-free interest rate	1.08	%	1.31	%	1.20	%
Expected dividend yield	0	%	0	%	0	%

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity

The following table summarizes the Company's non-vested restricted stock outstanding as of December 31, 2016 and changes during the year then ended:

	Shares		Weighted Average Grant Date Fair Value
Non-vested at beginning of year	154,801		$	85.84
Granted	193,036		$	57.11
Vested	(73,961	)	$	87.45
Forfeited	(7,506	)	$	79.30
Non-vested at end of year	266,370		$	64.76

Schedule of Share-based Compensation, Restricted Stock Units Award Activity

The following table summarizes the Company's non-vested restricted stock units outstanding as of December 31, 2016 and changes during the year then ended:

	Shares		Weighted Average Grant Date Fair Value
Non-vested at beginning of year	47,708		$	81.52
Granted	46,426		$	57.11
Vested	(21,018	)	$	84.37
Forfeited	(10,415	)	$	65.78
Non-vested at end of year	62,701		$	65.35

Share-based Compensation, Performance Shares Award Unvested Activity

The following table summarizes the 2016 performance-based restricted stock units at 100% of the award amounts as of December 31, 2016 and changes during the year then ended. Actual shares that will vest depend on the level of attainment of the performance based criteria. As of December 31, 2016, the Company expects to pay out 100% of the award.

	Shares	Weighted Average Grant Date Fair Value
Non-vested at beginning of year	—	$	—
Granted	27,602	$	57.12
Vested	—	$	—
Forfeited	—	$	—
Non-vested at end of year	27,602	$	57.12

The following table summarizes the 2015 and 2014 performance-based restricted stock units at the maximum award amounts as of December 31, 2016. Actual shares that will vest depend on the level of attainment of the performance based criteria. As of December 31, 2016, the threshold performance for any payout on the 2015 and 2014 awards granted has not been met.

	Shares	Weighted Average Grant Date Fair Value
Non-vested at beginning of year	28,810	$	52.55
Granted	—	$	—
Vested	—	$	—
Forfeited	—	$	—
Non-vested at end of year	28,810	$	52.55

Schedule of Performance-based Units Fair Value Assumptions

The following assumptions were used to estimate the grant date fair value of the performance-based restricted stock units granted during the years ended December 31, 2015 and 2014 and using the Monte Carlo simulation model:

	2015		2014
Volatility of the Company's common stock	24	%	25	%
Average volatility of peer group and S&P 500 companies	25	%	29	%
Average correlation coefficient of peer group and S&P 500 companies	0.5		0.6
Risk-free interest rate	0.98	%	0.81	%
Expected dividend yield	0	%	0	%
Expected term (in years)	3		3