Equity-Based compensation (Tables)

12 Months Ended

Dec. 31, 2017

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

Summary of Equity-Based Compensation Expense

The following table summarizes the compensation expense included in selling, general and administrative expenses in the Consolidated Statements of Earnings related to stock-based compensation plans:

	Years Ended December 31,
	2017		2016		2015
Service-Based RSUs	$	1,762	$	1,997	$	1,944
Performance-Based RSUs	2,350		665		1,235
Cash-settled awards	72		76		16
Total	$	4,184	$	2,738	$	3,195
Income tax benefit	1,573		1,029		1,201
Net	$	2,611	$	1,709	$	1,994

Schedule of Unrecognized Equity-Based Compensation Expense

The following table summarizes the unrecognized compensation expense related to non-vested RSUs by type and the weighted-average period in which the expense is to be recognized:

	Unrecognized compensation expense at December 31, 2017		Weighted- average period
Service-Based RSUs	$	1,079	1.11 years
Performance-Based RSUs	2,313		1.62 years
Total	$	3,392	1.46 years

Summary of Status of Equity-Based Compensation Plans

The following table summarizes the status of these plans as of December 31, 2017:

	2014 Plan	2009 Plan	2004 Plan	Directors' Plan
Awards originally available to be granted	1,500,000	3,400,000	6,500,000	N/A
Performance stock options outstanding	295,000	—	—	—
Maximum potential RSU and cash settled awards outstanding	725,759	122,600	57,391	9,620
Maximum potential awards outstanding	1,020,759	122,600	57,391	9,620
RSUs and cash settled awards vested and released	176,221	—	—	—
Awards available to be granted	303,020	—	—	—

Summary of Service-Based Restricted Stock Units

A summary of RSUs for all Plans is presented below:

	Units		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at January 1, 2017	554,478		$	13.37
Granted	57,740		24.32
Released	(201,918	)	13.85
Forfeited	(10,953	)	17.11
Outstanding at December 31, 2017	399,347		$	14.60	24.58	$	10,283
Releasable at December 31, 2017	259,811		$	12.48	33.88	$	6,690

Schedule of Weighted Average Grant Date Fair Value and Intrinsic Value of RSU's

	Years Ended December 31,
	2017		2016		2015
Weighted-average grant date fair value	$	24.32	$	15.07	$	17.31
Intrinsic value of RSUs released	$	4,485	$	1,520	$	2,933

Summary of Changes of Nonvested RSU's

A summary of nonvested RSUs is presented below:

	RSUs		Weighted Average Grant Date Fair Value
Nonvested at January 1, 2017	251,245		$	15.81
Granted	57,740		$	24.32
Vested	(158,496	)	$	16.40
Forfeited	(10,953	)	$	17.11
Nonvested at December 31, 2017	139,536		$	18.56

Schedule of Components of Performance-Based RSU's

A summary of PSUs for all Plans is presented below:

	Units		Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at January 1, 2016	201,900		$	16.48
Granted	123,919		$	23.83
Released	(43,275	)	$	21.66
Forfeited	(26,524	)	$	22.56
Added by performance factor	15,285		$	21.66
Outstanding at December 31, 2017	271,305		$	18.77	1.62	$	6,986
Releasable at December 31, 2017	—		$	—	—	$	—

The following table summarizes each grant of performance awards outstanding at December 31, 2017:

Description	Grant Date	Vesting Year	Vesting Dependency	Target Units  Outstanding	Maximum Number of Units to be Granted
2015-2017 Performance RSUs	February 5, 2015	2018	35% RTSR, 35% sales growth, 30% cash flow	62,000	124,000
2016-2018 Performance RSUs	February 16, 2016	2019	35% RTSR, 35% sales growth, 30% cash flow	92,840	185,680
2017-2019 Performance RSUs	February 9, 2017	2020	35% RTSR, 35% sales growth, 30% cash flow	71,796	143,592
2017-2019 Performance RSUs	February 9, 2017	2018- 2020	Operating Income	40,669	40,669
Single Crystal Performance RSUs	March 31, 2016	2019	Various	4,000	8,000
Total				271,305	501,941