Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2018

For the three and six months ended June 30, 2018 and 2017, we recorded share-based compensation and related tax benefits as follows:



	Three months ended June 30,						Six months ended June 30,
(Dollars in thousands)	2018			2017			2018			2017
Share-based compensation expense	$	11,944		$	9,892		$	22,467		$	19,095
Income tax benefit related to share-based compensation expense	(2,743		)	(3,349		)	(5,060		)	(6,364		)

As of June 30, 2018, unrecognized share-based compensation expense was as follows:



(Dollars in thousands)	Unrecognized Expense		Weighted Average Expected Recognition Period - in Years
Stock options	$	15,039	3.10
Restricted stock units	81,376		2.91
Total unrecognized share-based compensation expense	$	96,415

The table below provides stock option information related to the 2006 Equity Incentive Plan for the six months ended June 30, 2018:



	Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life - in Years	Aggregate Intrinsic Value of In-The- Money Options
Outstanding at December 31, 2017	808,049		$	105.68
Granted	87,352		305.22
Exercised	(156,580	)	84.83
Forfeited	(1,926	)	130.69
Expired	(2,337	)	60.37
Outstanding at June 30, 2018	734,558		133.93		3.92	$	115,185,279
Vested and expected to vest at June 30, 2018	710,108		131.27		3.85	113,119,954
Exercisable at June 30, 2018	449,728		97.80		2.82	85,881,104

The table below provides information for restricted stock units under the 2006 Equity Incentive Plan for the six months ended June 30, 2018:



	Shares		Weighted Average Grant Date Fair Value
Nonvested at December 31, 2017	637,667		$	135.86
Granted	185,292		301.56
Vested	(206,997	)	130.29
Forfeited	(21,028	)	148.43
Nonvested at June 30, 2018	594,934		188.96