Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

Share-based Compensation

Summary of share-based compensation expense

	Three months ended
	March 31,
(in thousands)	2018		2017
Share-based compensation	$	6,295	9,047

Summary of weighted average assumptions, and weighted average fair value of options

		Three months ended
		March 31,
	2018			2017
Number of options granted		341,659		481,712
Weighted average exercise price	$	87.08		54.47
Risk-free interest rate		2.55	%	1.77	%
Expected volatility		21.80	%	21.72	%
Expected term (years)		4.8		4.6
Dividend yield		0.60	%	0.73	%
Weighted average fair value	$	19.34		10.73

Nonvested Share Awards

Share-based Compensation

Summary of shares granted

		Three months ended March 31,
	2018		2017
Number of shares granted		292,359	282,860
Market value (in millions)	$	26.1	15.4

Performance Based Awards

Share-based Compensation

Summary of shares granted

Year Awarded	Performance Period Ending	Performance Measure	Number of Shares Granted	Period Expensed Through
2018	December 2020	Adjusted Diluted EPS1	79,218	December 2020
2018	December 2018	Net Revenue and Adjusted Diluted EPS1	84,444	December 2020
2018	December 2019	Non-financial Operational Metric	11,304	December 2020
2017	December 2019	Adjusted Diluted EPS1	99,492	December 2019
2017	December 2017	Net Revenue and Adjusted Diluted EPS1	146,094	December 2019

¹ Adjusted Diluted EPS is adjusted earnings divided by weighted average diluted shares outstanding used for diluted EPS calculations.Adjusted earnings is net income excluding the after-tax impact of share-based compensation expenses, amortization of acquisition intangibles, merger and acquisition expenses for completed acquisitions and litigation claims, judgments or settlement expenses and related legal expenses.

Market Based Share Awards

Share-based Compensation

Summary of shares granted

Year Awarded	Performance Period Ending	Performance Measure	Number of Shares Granted	Period Expensed Through
2018	December 2020	TSR	33,940	December 2020
2017	December 2019	TSR	42,644	December 2019