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Equity-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Share-based Compensation [Abstract]

Summary of Compensation Expense Connection with Awards

The Company recognized the following compensation expense in connection with awards that vested under the 2018 Plan, the 2015 Plan, the Prior Plan, and the Non-Employee Directors Plan along with the related tax benefits recognized during the years ended December 31 (in thousands):

	2018				2017				2016
Expense recognized under the Prior Plan	$	569			$	1,059			$	1,937
Expense recognized under the 2015 Plan	7,988				5,643				3,993
Expense recognized under the 2018 Plan	188				—				—
Expense recognized under the Non-Employee Directors Plan	444				420				443
Total stock compensation expense	$	9,189			$	7,122			$	6,373
Tax benefits recognized related to stock compensation expense	$	2,509			$	2,133			$	2,485

Schedule of Number of Awards and Weighted Average Grant Date Fair Value

The following table provides the number of stock options, stock units, and unrestricted shares granted during the years ended December 31, along with the weighted-average grant-date fair value of each award:

	2018							2017							2016
Awards	Number of Awards			Weighted Average Grant Date Fair Value				Number of Awards			Weighted Average Grant Date Fair Value				Number of Awards			Weighted Average Grant Date Fair Value
Options	—			$	—			25,000			$	12.85			—			$	—
Deferred stock units	10,255			$	35.96			10,170			$	34.42			11,945			$	29.30
Common shares	2,113			$	35.50			2,034			$	34.42			3,185			$	29.30
Restricted stock units	116,174			$	36.61			133,548			$	36.56			141,982			$	25.44
Performance stock units	135,929			$	33.63			108,748			$	42.72			—			$	—

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

The following table provides the weighted average assumptions used to value stock options issued during the year ended December 31:

Year of Grant		Fair Value				Expected Life (in years)		Expected Stock Volatility			Risk-free Interest Rate			Expected Dividend Yield
2017		$	12.85			4.00		35.7	%		1.7	%		—	%

Summary of Ranges of Outstanding and Exercisable Options

The following table summarizes the ranges of outstanding and exercisable options at December 31, 2018:

Range of Exercise Prices	Options Outstanding			Weighted Average Remaining Contractual Life (in years)		Weighted Average Exercise Price				Options Exercisable			Weighted Average Exercise Price
$8.90 – $9.32	18,938			1.70		$	8.90			18,938			$	8.90
$9.33 – $11.73	70,721			2.70		$	9.74			70,721			$	9.74
$11.74 – $19.58	20,100			0.70		$	13.72			20,100			$	13.72
$19.59 - $32.49	25,000			7.00		$	25.44			25,000			$	25.44
$32.50 - $43.05	25,000			8.14		$	42.35			—			$	—
	159,759									134,759

Summary of Stock Options Transactions

The following table summarizes information about stock option transactions:

	Options			Weighted Average Exercise Price				Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Balance at January 1, 2016	458,349			$	16.57
Exercised	(175,125	)		19.08
Forfeited	(6,000	)		18.22
Balance at December 31, 2016	277,224			$	14.95
Granted	25,000			42.35
Exercised	(42,058	)		16.02
Forfeited	(12,500	)		25.44
Balance at December 31, 2017	247,666			$	17.01
Exercised	(87,907	)		15.75
Balance at December 31, 2018	159,759			$	17.70			6.13		$	3,026,930

Summary of Information About Restricted Stock Units and Weighted Average Grant Date Fair Value

The following table summarizes information about non-vested restricted stock units, performance stock units (that will convert to shares upon vesting) and common and restricted shares:

	Restricted Stock Units			Weighted Average Grant Date Fair Value				Common and Restricted Shares			Weighted Average Grant Date Fair Value				Performance Stock Units (1)			Weighted Average Grant Date Fair Value				Deferred Stock Units (2)			Weighted Average Grant Date Fair Value
Balance at December 31, 2017	441,816			$	23.96			4,258			$	17.30			480,462			$	24.68			22,115			$	31.65
Granted	116,174			36.61				2,113			35.50				135,929			33.63				10,255			35.96
Vested	(137,020	)		22.72				(6,371	)		23.34				(323,118	)		18.57				(5,127	)		32.18
Forfeited	(25,617	)		31.70				—			—				(57,788	)		41.59				—			—
Balance at December 31, 2018	395,353			$	27.61			—			$	—			235,485			$	33.78			27,243			$	33.18

Aggregate Intrinsic Value of Options Exercised and Aggregate Fair Value of Restricted Stock Units and Restricted Shares that Vested

The following table sets forth the aggregate intrinsic value of options exercised and aggregate fair value of restricted stock units and restricted shares that vested during the years ended December 31 (in thousands):

	2018				2017				2016
Aggregate intrinsic value of options exercised	$	2,128			$	628			$	2,439
Aggregate fair value of vested restricted stock units	$	5,307			$	6,756			$	4,368
Aggregate fair value of vested common and restricted shares	$	149			$	70			$	247
Aggregate fair value of vested deferred stock units	$	369			$	350			$	443

PSUs Eligible for Conversion to Cash

The following table provides the number of PSUs which will convert to cash for the years ending December 31:

	2016
Awards	Number of Units (2)			Grant Date Fair Value (in $000s)
Performance stock units (1)	128,000			$	3,100

(1) There were no performance stock units that convert to cash granted to participants in 2018 and 2017.

(2) The participants earned 200% of target aggregating 256,000 PSUs earned. This award will be converted to cash and will be paid to participants in the first quarter of 2019 at the trailing 90-day closing price of the Company's common stock as of December 31, 2018.

Schedule of Compensation Expense Recognized from Change in Fair Value and Vesting of Performance Stock Units

The following table summarizes the compensation expense recognized from the change in fair value and vesting of cash settled performance stock units awarded for the years ended December 31 (in thousands):

	2018				2017				2016
Performance stock unit compensation expense	$	2,846			$	3,591			$	10,377

Cash Paid to Settle Liability Awards

The following table provides the number of restricted stock units credited to active participant accounts, balance of vested and unvested restricted stock units within active participant accounts, payments made with respect to restricted stock units issued under the MSPP, and MSPP expense during years ended December 31:

	2018				2017				2016
Restricted stock units credited	66,843				84,299				198,155
Restricted stock units balance, vested and unvested	387,870				389,189				646,669
Share-based liabilities paid, in thousands	$	5,232			$	6,058			$	3,137
MSPP expense, in thousands	$	4,809			$	2,432			$	8,565

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