Note 15 - Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2021

Notes Tables

Share-based Payment Arrangement, Option, Activity [Table Text Block]

						Weighted-
						average
				Weighted-		remaining		Aggregate
	Number			average		contractual		intrinsic
	of shares			exercise		term		value
	(in thousands)			price		(in years)		(in thousands)
Options outstanding as of December 31, 2020		17,095		$	21.60
Granted
Exercised		(4,061	)		19.96
Forfeited and expired		(232	)		22.50
Options outstanding as of June 30, 2021		12,802			22.10		7.00	$	240,623
Options expected to vest as of June 30, 2021		12,675			22.12		6.99		238,009
Options exercisable as of June 30, 2021		7,310			20.96		5.85		145,729

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three months ended
	June 30,
	2020
Expected volatility		32.9	%
Weighted-average volatility		32.9	%
Expected dividends		4.48	%
Risk-free rate		0.5	%
Average risk-free rate		0.5	%
Expected term (in years)		7.4
Pre-vesting executive departure rate		0.6	%
Pre-vesting non-executive departure rate		2.5	%

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

				Weighted
	Number			average
	of shares			grant-date
	(in thousands)			fair value
Non-vested shares and share units at December 31, 2020		12,943		$	22.87
Granted		1,384			42.11
Vested		(3,414	)		22.61
Forfeited		(321	)		23.45
Non-vested shares and share units at June 30, 2021		10,592		$	25.45

Share-based Payment Arrangement, Performance Shares, Activity [Table Text Block]

				Weighted
	Number			average
	of shares			grant-date
	(in thousands)			fair value
Non-vested share units at December 31, 2020		1,765		$	28.06
Granted		1,222			38.82
Vested		(119	)		28.06
Forfeited		(56	)		32.30
Non-vested share units at June 30, 2021		2,812		$	32.65