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The maximum number of equity awards an employee may receive as a percentage of the target number.

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The amount per share required to be paid by employees upon the vesting of equity instruments other than options.

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The minimum number of equity awards an employee may receive as a percentage.

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Represents the intrinsic value for stock purchased under the employee stock purchase plan.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash inflow associated with the amount received from the stock plan during the period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Note 3 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended
	Jun. 11, 2020	Feb. 29, 2024	Mar. 31, 2024	Mar. 31, 2023	Aug. 16, 2023	Nov. 13, 2014
Share Price (in dollars per share)		$ 632.98	$ 677.42
Proceeds from Stock Plans			$ 4,606	$ 3,737
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested			403,000	$ 141,600
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding			1,100,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 339,500
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years
Time-Based RSUs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)			21,000
Time-Based RSUs [Member] \| Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)			21,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			4 years
Time-Based RSUs [Member] \| Director [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			1 year
PSU 2024 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Price Per Share Payable Upon Vesting of Equity Instruments Other than Options (in dollars per share)			$ 30
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)			3 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate			49.40%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			4.10%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.80%
PSU 2024 [Member] \| Executive Officer [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		50,000
Maximum Stock Compensation Costs			$ 154,300
PSU 2024 [Member] \| Executive Officer [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Percentage Allowed		300.00%
PSU 2024 [Member] \| Executive Officer [Member] \| Share-Based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Percentage Allowed		100.00%
PSU 2024 [Member] \| Executive Officer [Member] \| Share-Based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Percentage Allowed		50.00%
PSU 2024 [Member] \| Non-Executive Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		11,000
Maximum Stock Compensation Costs			$ 17,700
PSU 2024 [Member] \| Non-Executive Employees [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Percentage Allowed		300.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Minimum Percentage Allowed		200.00%
PSU 2024 [Member] \| Non-Executive Employees [Member] \| Vesting First Quarter of 2026 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		50.00%
The2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)						5,500,000
Amended and Restated 2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	10,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)			3,900,000
The 2004 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)					4,400,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)			4,400,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 1,100
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)			11,000	9,000
Employee Stock Purchase Plan Shares Issued, Intrinsic Value			$ 3,500	$ 700
Proceeds from Stock Plans			$ 4,600	$ 3,700