Stock-Based Compensation and Stock Awards (Tables)

12 Months Ended

Dec. 31, 2018

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

Schedule of Option Activity

Option activity for the year ended December 31, 2018 was as follows:

	Number of Options		Weighted Average Price		Aggregate Intrinsic Value (in millions)	Weighted Average Remaining Contractual Life (in years)
Outstanding at December 31, 2017	280,212		$	59.84
Granted	—		—
Exercised	(35,375	)	31.59
Forfeited	(20,750	)	67.71
Outstanding at December 31, 2018	224,087		$	63.57	—	2.1
Exercisable at year-end	224,087		$	63.57	—	2.1

Summary of RSA Activity

The Company’s RSA activity and related information is presented below:

	Restricted Stock		Weighted-average Grant Date Fair Value
Unvested at December 31, 2017	397,298		$	46.76
Granted	197,380		41.93
Vested	(169,434	)	49.73
Forfeited	(22,065	)	46.17
Unvested at December 31, 2018	403,179		$	43.18

Schedule of Valuation Assumptions

Assumptions used in the Monte Carlo simulation are as follows:

	2018	2017	2016
Grant date	October 28, 2018	October 28, 2017	October 28, 2016
Performance period	October 1, 2018 to September 30, 2021	October 1, 2017 to September 30, 2020	October 1, 2016 to September 30, 2019
Volatility	32.6%	34.0%	32.5%
Risk-free interest rate	2.9%	1.7%	1.0%
Grant date price	$43.09	$41.50	$48.45

Summary of PSA Activity

The Company’s Performance Unit activity and related information is presented below:

	Number of Performance Units		Weighted Average Grant Date Fair Value Per Unit
Nonvested balance at December 31, 2017	264,274		$	59.97
Granted	88,179		54.62
Vested	(48,072	)	79.00
Forfeited	(16,288	)	79.00
Nonvested balance at December 31, 2018	288,093		$	54.22

Schedule of DSA Activity

The Company's DSA activity for the year ended December 31, 2018 is presented below:

	DSA Number of Shares		Weighted Average Grant Date Fair Value Per Share
Non-vested balance at December 31, 2017	17,514		$	54.80
Granted	9,539		48.32
Vested	(8,174	)	58.47
Forfeited	—		—
Nonvested balance at December 31, 2018	18,879		$	49.93

Schedule of Information for Stock Option Plans

The following table summarizes information for equity compensation plans in effect as of December 31, 2018:

	Number of securities to be issued upon exercise of outstanding options (1)	Weighted-average exercise price of outstanding options		Number of securities remaining available for future issuance under equity compensation plan (excluding securities reflected in column (a))
Plan category	(a)	(b)		(c)
Equity compensation plans approved by stockholders
Stock options	224,087	$	63.57	1,279,330
Total	224,087	$	63.57	1,279,330

(1) Excludes 422,058 shares of unvested RSAs and DSAs and 288,093 of unvested Performance Units, which were granted pursuant to the 2017 Plan and the 2004 Plan, both of which were approved by the stockholders.