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Note 10 - Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Share-Based Payment Arrangement, Expense		$ 469.0	$ 448.0
Share-Based Payment Arrangement, Expense, Tax Benefit		113.0	$ 108.0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 1.7
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		2 years 1 month 13 days
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		0	0
The 2014 Long-term Incentive Plan [Member] \| Stock Appreciation Rights (SARs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	54,947			122,542
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 8.97			$ 8.40
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	7 years			5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)	10 years			10 years
The 2014 Long-term Incentive Plan [Member] \| Stock Appreciation Rights (SARs) [Member] \| Vesting Per Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage	14.30%			20.00%
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		5 years