Equity-based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2018

Equity-based Compensation Plans

Schedule of equity-based compensation expense classified with the consolidated statements of operations

	Year Ended December 31,
($ in thousands)	2018		2017		2016
Equity-based compensation expense:
Costs applicable to revenue	$	820	$	386	$	90
Selling, general, and administrative		13,268		4,723		1,507
Total equity-based compensation expense	$	14,088	$	5,109	$	1,597
Total income tax benefit recognized related to equity-based compensation	$	1,350	$	619	$	125

Schedule of valuation assumptions used

	2016
Expected term (years) (1)	6.3
Expected volatility (2)	36.1	%
Risk-free interest rate (3)	1.5	%
Dividend yield (4)	1.1	%

(1) Expected term represents the estimated period of time until an award is exercised and was determined using the simplified method.

(2) Expected volatility is based on the historical volatility of a selected peer group over a period equivalent to the expected term.

(3) The risk-free rate is an interpolation of yields on U.S. Treasury securities with maturities equivalent to the expected term.

(4) The dividend yield was based on the Company’s expectation at the time of grant to declare quarterly dividends of $0.06 per share.

Summary of stock option activity

							Weighted Average
					Aggregate		Remaining
	Stock Options		Weighted Average		Intrinsic Value		Contractual Life
	(in thousands)		Exercise Price		(in thousands)		(years)
Outstanding at December 31, 2017		953	$	21.86
Exercised		(7)	$	22.00
Forfeited		(61)	$	22.00
Outstanding at December 31, 2018		885	$	21.85	$	—		7.7
Options exercisable at December 31, 2018		409	$	21.86	$	—		7.6

Summary of restricted stock unit activity

	Restricted		Weighted Average
	Stock Units		Grant Date
	(in thousands)		Fair Value
Outstanding at December 31, 2017		1,247	$	37.65
Granted		725	$	25.73
Vested		(298)	$	36.15
Forfeited		(248)	$	34.70
Outstanding at December 31, 2018		1,426	$	32.42