Note 3 - Share-based Compensation

6 Months Ended

Jun. 30, 2018

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

3 .	Share-b ased Compensation

The following table summarizes the components of our share-based compensation program expense (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
Restricted share units:
Pretax compensation expense	$	9,844	$	8,873	$	18,435	$	17,010
Tax benefit		2,559		3,314		4,793		5,596
Restricted share unit expense, net of tax	$	7,285	$	5,559	$	13,642	$	11,414

Performance share units:
Pretax compensation expense	$	4,121	$	3,067	$	7,566	$	6,100
Tax benefit		1,071		1,146		1,967		2,007
Performance share unit expense, net of tax	$	3,050	$	1,921	$	5,599	$	4,093

As of

June 30, 2018,

we had

$68.5

million and

$20.7

million of total unrecognized compensation expense related to restricted share units and performance share units, respectively, that is to be recognized over the remaining weighted-average period of approximately

3.6

years for restricted share units and

2.5

years for performance share units. During the

six

months ended

June 30, 2018,

we issued

4,141

shares for vested restricted share units. Of this total,

709

shares for vested restricted share units were issued during the

second

quarter

2018.