Note 3 - Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Restricted share units:
Pretax compensation expense	$	8,873	$	8,939	$	17,010	$	16,907
Tax benefit		3,314		3,397		5,596		6,425
Restricted share unit expense, net of tax	$	5,559	$	5,542	$	11,414	$	10,482
Performance share units:
Pretax compensation expense	$	3,067	$	3,004	$	6,100	$	6,008
Tax benefit		1,146		1,142		2,007		2,283
Performance share unit expense, net of tax	$	1,921	$	1,862	$	4,093	$	3,725