Nature of Business and Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Deferred Tax Assets, Valuation Allowance	$ 2,787	$ 3,196
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	(164,409)	(148,406)
Gains and (losses) netted against other income, net	(800)	(1,300)	$ (200)
Other Inventory, Demo, Gross	30,400	35,200
Advertising costs	10,700	13,000	$ 19,500
Carrying value of cost-basis investments	19,900	$ 17,100
Impairment charge - Cost-basis Investments	$ 4,100
Effect of stock-based compensation awards, shares excluded for purposes of diluted earnings per share	33	10	39
Unrecognized stock-based compensation costs, net of estimated forfeitures	$ 59,500
Weighted average period of unrecognized stock-based compensation costs, net of estimated forfeitures	2 years
Estimated forfeiture rate	5.00%
Net cash provided by operating activities	$ 370,372	$ 374,157	$ 308,252
Net cash (used) provided by financing activities	54,040	(318,944)	(132,612)
Excess Tax Benefit from Share-based Compensation, Financing Activities	(11,993)	(16,228)	$ (10,731)
Operating Lease, Right-of-Use Asset	35,479			$ 31,900
Operating Lease, Liability	39,291			$ 34,200
Level 1
Cash equivalents at fair value	$ 700	$ 200,000
Time-vested restricted stock unit
Restricted stock units granted	867,000	594	773
Time-vested and performance-based restricted stock unit
Weighted average grant date fair value per share	$ 50.45	$ 52.93	$ 36.20
Performance-based restricted stock unit [Domain]
Total fair value of awards granted	$ 7,800		$ 9,900
Restricted Stock Unit Awards
Total fair value of awards granted	$ 51,578	$ 40,675	$ 37,906
Performance-based restricted stock unit [Member]
Restricted stock units granted	158,000	177	283
Weighted average grant date fair value per share	$ 49.57	$ 52.32	$ 35.08
Total fair value of awards granted		$ 9,200
Stock Option Awards
Cash received from the exercise of stock options	$ 21,200	23,700	$ 53,500
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	$ 4,800	$ 8,700	$ 3,000

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Share based Compensation Arrangement by Share based Payment Award, Equity Instruments Other than Options, Grants in Period, Aggregate Fair Value

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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