Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

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

Components of Share-Based Compensation Expense by Type of Award

The following table lists the components of share-based compensation cost by type of award.

	Year Ended December 31,
	2017		2016		2015
Stock options	$	1,078	$	687	$	984
Restricted stock		1,968		2,061		2,623
Performance share units		2,450		1,187		432
Share-based compensation	$	5,496	$	3,935	$	4,039

Weighted Average Assumptions Relevant to Determining the Fair Value at the Dates of Grant and Stock Option Modification

The following table shows the weighted average assumptions relevant to determining the fair value of stock options granted in each year.

	2017			2016			2015
Expected term		6 years			6 years			6 years
Risk free interest rate		2.03	%		1.43	%		1.43	%
Dividend yield		1.16	%		2.48	%		1.11	%
Expected volatility		56.56	%		59.23	%		59.22	%
Expected forfeiture rate		3.00	%		3.00	%		3.00	%

Reconciliation of Option Activity

The following table summarizes option activity for the year ended December 31, 2017.

Options	Shares (in thousands)			Weighted- Average Exercise Price (per share)		Weighted- Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at January 1, 2017		897		$	12.22
Granted		126			24.20
Exercised		(263	)		11.84			$	3,784
Forfeited or expired		(14	)		14.34
Outstanding at December 31, 2017		746		$	14.33		6.2	$	9,900	(1)
Exercisable at December 31, 2017		573		$	12.75		5.5	$	8,506	(1)

(1) The intrinsic value is the amount by which the closing market price of our stock as of December 31, 2017, was greater than the exercise price of any individual option grant.

Reconciliation of Restricted Stock Option Activity

The following table summarizes the status of unvested restricted stock awards as of December 31, 2017, and changes during the year then ended.

	Nonvested Restricted Shares (in thousands)			Weighted Average Grant- Date Fair Value
Nonvested at January 1, 2017		202		$	15.01
Granted		85		$	24.29
Vested		(135	)	$	15.63
Forfeited		—		$	—
Nonvested at December 31, 2017		152		$	19.21

Schedule of Performance Based Awards Goals with Respect to TSR and ROIC

The following table presents the goals with respect to TSR and ROIC for each award.

TSR:

	Threshold Performance (50% of Shares)		Target Performance (100% of Shares)		Maximum Performance (150% of Shares)
2017 grants		35th Percentile		50th Percentile		75th Percentile
2016 grants		35th Percentile		50th Percentile		75th Percentile
2015 grants		35th Percentile		50th Percentile		75th Percentile

ROIC:

	Threshold Performance (35% of Shares)			Target Performance (100% of Shares)			Maximum Performance (150% of Shares)
2017 grants		15	%		17.5	%		20	%
2016 grants		15.5	%		18	%		20.5	%
2015 grants		11	%		12.5	%		14	%

Schedule of Number of Awards Granted and Grant Date Fair Value of Each Award in Periods

The following table presents the number of awards granted and the grant date fair value of each award in the periods presented.

	TSR Awards				ROIC Awards
Award Year	Shares (in thousands)		Grant Date Fair Value		Shares (in thousands)		Grant Date Fair Value
2017		46	$	29.84		53	$	24.20
2016		101	$	9.38		101	$	11.31
2015		36	$	28.61		36	$	25.16

Summary of Status of Unvested PSU Awards

The following table summarizes the status of unvested PSU awards as of December 31, 2017, and changes during the year then ended.

	Nonvested TSR Awards					Nonvested ROIC Awards
	Shares (in thousands)			Weighted Average Grant-Date Fair Value		Shares (in thousands)			Weighted Average Grant-Date Fair Value
Nonvested at January 1, 2017		124		$	14.33		124		$	14.87
Change in Vesting Estimate (1)		—		$	—		16		$	25.16
Granted		46		$	29.84		53		$	24.20
Vested		(32	)	$	28.61		(48	)	$	25.16
Forfeited		(8	)	$	19.19		(9	)	$	18.03
Nonvested at December 31, 2017		130		$	16.60		136		$	16.27

(1) Represents additional shares expected to be issued in settlement of ROIC Awards that were granted in 2015.