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The number of available shares expired under the plan.

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Price target for market-based awards.

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Number of individual price target.

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Price of a single share of a number of saleable stocks that the employee pays to the company upon vesting of the shares.

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The expense to be recognized over the period which an employee is required to provide service in exchange for the equity-based payment award.

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Number of individual tranches in a single share-based payment award plan.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Note 7 - Stock-based Compensation (Details Textual)			1 Months Ended												3 Months Ended	9 Months Ended	12 Months Ended
Note 7 - Stock-based Compensation (Details Textual)	Dec. 31, 2015 $ / shares shares	Nov. 12, 2014 shares	Feb. 28, 2018 USD ($) shares	Feb. 28, 2017 USD ($) $ / shares shares	Jul. 31, 2016 $ / shares shares	Feb. 29, 2016 USD ($) $ / shares shares	Dec. 31, 2015 $ / shares	Feb. 28, 2015 USD ($) shares	Jul. 31, 2014 USD ($) shares	Apr. 30, 2014 shares	Mar. 31, 2014 shares	Feb. 28, 2014 shares	Dec. 31, 2013 $ / shares shares	Feb. 28, 2013 shares	Mar. 31, 2016 USD ($)	Sep. 30, 2017	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares	Nov. 13, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period																	666,000	1,349,000	1,198,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross																	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value \| $																	$ 700,000	$ 3,700,000	$ 18,600,000
Proceeds from Stock Options Exercised \| $																	150,000	1,344,000	7,744,000
Proceeds from Stock Plans \| $																	2,701,000	2,463,000	2,227,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested \| $																	74,000,000	$ 62,900,000	$ 49,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding \| $																	$ 430,600,000
Share Price \| $ / shares																	$ 112.36
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $																	$ 75,900,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition																	3 years
Time-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period																	81,000	133,000	271,000
2017 PSU's [Member]
Share Price \| $ / shares				$ 89.37
Purchase Price Per Share \| $ / shares				$ 30
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term				2 years 219 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate				28.60%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate				1.30%
2016 PSU's [Member]
Share Price \| $ / shares					$ 70.98	$ 58.98
Purchase Price Per Share \| $ / shares						$ 20
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term					2 years 109 days	2 years 219 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate					29.60%	31.10%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate					0.70%	0.90%
2016 PSU's [Member] \| Subsequent Event [Member]
Total PSU Earned			651,000
Actual Stock Compensation Costs \| $			$ 26,100,000
2015 MPSUs [Member]
Share Price \| $ / shares	$ 61.35						$ 61.35												$ 61.35
PSUs Earn-Out Percentage							500.00%
Maximum Stock Compensation Costs \| $																			$ 24,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate																			33.20%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate																			1.30%
Number of MPSU Tranches							4
Share-based Compensation Arrangement by Share-based Payment Award, Post-Award Vesting Period, Restriction Period on Sales							2 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Discount for Postvesting Restrictions																			7.80%
2015 MPSUs [Member] \| Share-based Compensation Award, Tranche One [Member]
Maximum Stock Compensation Costs \| $																			$ 8,300,000
Number of Price Targets							5
Stock Price Targets Achieved																5
2015 MPSUs [Member] \| Second, Third, and Fourth Tranches [Member]
Number of Price Targets							5
Total number of performance conditions							6
2015 MPSUs [Member] \| Share-based Compensation Award, Tranche Two [Member]
Maximum Stock Compensation Costs \| $																			4,500,000
2015 MPSUs [Member] \| Share-based Compensation Award, Tranche Three [Member]
Maximum Stock Compensation Costs \| $																			5,200,000
2015 MPSUs [Member] \| Share-based Compensation Award, Tranche Four [Member]
Maximum Stock Compensation Costs \| $																			$ 6,600,000
2015 MPSUs [Member] \| Minimum [Member] \| Share-based Compensation Award, Tranche One [Member]
Market Awards Price Targets \| $ / shares							$ 71.36
2015 MPSUs [Member] \| Minimum [Member] \| Share-based Compensation Award, Tranche Two [Member]
Market Awards Price Targets \| $ / shares							89.56
2015 MPSUs [Member] \| Minimum [Member] \| Share-based Compensation Award, Tranche Three [Member]
Market Awards Price Targets \| $ / shares							120.80
2015 MPSUs [Member] \| Maximum [Member] \| Share-based Compensation Award, Tranche One [Member]
Market Awards Price Targets \| $ / shares							95.57
2015 MPSUs [Member] \| Maximum [Member] \| Share-based Compensation Award, Tranche Two [Member]
Market Awards Price Targets \| $ / shares							106.81
2015 MPSUs [Member] \| Maximum [Member] \| Share-based Compensation Award, Tranche Three [Member]
Market Awards Price Targets \| $ / shares							$ 135.48
2013 MSU's [Member]
Share Price \| $ / shares													$ 31.73							$ 31.73
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																				5 years
PSUs Earn-Out Percentage																				500.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate																				38.70%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate																				1.60%
Actual Stock Compensation Costs \| $																				$ 38,200,000
Total MSUE arned																			1,800,000
2013 MSU's [Member] \| Minimum [Member]
Market Awards Price Targets \| $ / shares																				$ 40
2013 MSU's [Member] \| Maximum [Member]
Market Awards Price Targets \| $ / shares																				$ 56
Employee Stock Option [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $																	$ 0
Proceeds from Stock Options Exercised \| $																	$ 100,000	$ 1,300,000	$ 7,700,000
Chief Financial Officer [Member] \| Restricted Stock Units (RSUs) [Member] \| Selling, General and Administrative Expenses [Member]
Share-based Compensation Adjustment \| $															$ 2,900,000
Employees [Member] \| Time-Based RSUs [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																	3 years
Employees [Member] \| Time-Based RSUs [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																	4 years
Director [Member] \| Time-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																	1 year
Executive Officer [Member] \| 2017 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				200,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				2 years
PSUs Earn-Out Percentage				300.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				50.00%
Maximum Stock Compensation Costs \| $				$ 36,300,000
Executive Officer [Member] \| 2016 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					12,000	285,000
PSUs Earn-Out Percentage						300.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage						50.00%
Executive Officer [Member] \| 2015 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period								172,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period								2 years
PSUs Earn-Out Percentage								300.00%
Total PSU Earned				432,000
Actual Stock Compensation Costs \| $				$ 21,000,000
Executive Officer [Member] \| 2015 PSU's [Member] \| Vesting in The First Quarter of 2017 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage								50.00%
Executive Officer [Member] \| 2015 MPSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	86,000
Executive Officer [Member] \| 2014 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period												252,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												2 years
PSUs Earn-Out Percentage												300.00%
Total PSU Earned						694,000
Actual Stock Compensation Costs \| $						$ 20,700,000
Executive Officer [Member] \| 2014 PSU's [Member] \| Vesting in the First Quarter of 2016 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage												50.00%
Executive Officer [Member] \| 2013 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period														220,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period														2 years
PSUs Earn-Out Percentage														300.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage														50.00%
Total PSU Earned								622,000
Actual Stock Compensation Costs \| $								$ 15,000,000
Executive Officer [Member] \| 2013 MSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period													276,000
Non-Executive Employees [Member] \| 2017 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				48,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				2 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				50.00%
Maximum Stock Compensation Costs \| $				$ 7,100,000
Non-Executive Employees [Member] \| 2017 PSU's [Member] \| Minimum [Member]
PSUs Earn-Out Percentage, First Tier				200.00%
Non-Executive Employees [Member] \| 2017 PSU's [Member] \| Maximum [Member]
PSUs Earn-Out Percentage, Second Tier				300.00%
Non-Executive Employees [Member] \| 2016 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period						64,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						2 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage						50.00%
Non-Executive Employees [Member] \| 2016 PSU's [Member] \| Subsequent Event [Member]
Total PSU Earned			128,000
Actual Stock Compensation Costs \| $			$ 5,100,000
Non-Executive Employees [Member] \| 2016 PSU's [Member] \| Minimum [Member]
PSUs Earn-Out Percentage, First Tier						200.00%
Non-Executive Employees [Member] \| 2016 PSU's [Member] \| Maximum [Member]
PSUs Earn-Out Percentage, Second Tier						300.00%
Non-Executive Employees [Member] \| 2015 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period								58,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period								2 years
Total PSU Earned				118,000
Actual Stock Compensation Costs \| $				$ 5,700,000
Non-Executive Employees [Member] \| 2015 PSU's [Member] \| Vesting in The First Quarter of 2017 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				50.00%
Non-Executive Employees [Member] \| 2015 PSU's [Member] \| Minimum [Member]
PSUs Earn-Out Percentage								200.00%
Non-Executive Employees [Member] \| 2015 PSU's [Member] \| Maximum [Member]
PSUs Earn-Out Percentage								300.00%
Non-Executive Employees [Member] \| 2015 MPSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	41,000
Non-Executive Employees [Member] \| 2014 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period										61,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period										2 years
Total PSU Earned						103,000
Actual Stock Compensation Costs \| $						$ 3,700,000
Non-Executive Employees [Member] \| 2014 PSU's [Member] \| Vesting in the Second Quarter of 2016 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage										50.00%
Non-Executive Employees [Member] \| 2014 PSU's [Member] \| Minimum [Member]
PSUs Earn-Out Percentage										200.00%
Non-Executive Employees [Member] \| 2014 PSU's [Member] \| Maximum [Member]
PSUs Earn-Out Percentage										300.00%
Non-Executive Employees [Member] \| 2013 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period														91,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period														2 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage														50.00%
Total PSU Earned								154,000
Actual Stock Compensation Costs \| $								$ 3,000,000
Non-Executive Employees [Member] \| 2013 PSU's [Member] \| Minimum [Member]
PSUs Earn-Out Percentage														200.00%
Non-Executive Employees [Member] \| 2013 PSU's [Member] \| Maximum [Member]
PSUs Earn-Out Percentage														300.00%
Non-Executive Employees [Member] \| 2013 MSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period													84,000
Sensima Employees [Member] \| 2014 PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period									47,000
Stock Granted, Value, Share-based Compensation, Gross \| $									$ 2,000,000
Maximum PSU Earn Out \| $									$ 8,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Expense to be Recognized over Requisite Service Period \| $																	$ 2,000,000
Sensima Employees [Member] \| 2014 PSU's [Member] \| Share-based Compensation Award, Tranche One [Member] \| Sensima [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage									50.00%
Sensima Employees [Member] \| 2014 PSU's [Member] \| Remaining Half of RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period									2 years
2004 Employee Stock Plan [Member]
Share-basedCompensation Arrangement by Share-based Payment Award, Other Than Options, Percent Increases in Period											5.00%
Share-based Compensation Arrangement by Share-based Payment Award, Automatic Increase Shares											2,400,000
Expired Shares under Plan		2,900,000
The2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																					5,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant																	3,200,000
The 2004 Employee Stock Purchase Plan [Member]
Share-basedCompensation Arrangement by Share-based Payment Award, Other Than Options, Percent Increases in Period																	2.00%
Share-based Compensation Arrangement by Share-based Payment Award, Automatic Increase Shares																	1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant																	4,600,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $																	$ 92,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee																	2,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares per Employee Value																	25,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans																		53,000	56,000
Employee Stock Purchase Plan Shares Issued, Intrinsic Value \| $																		$ 1,000,000	$ 600,000
Proceeds from Stock Plans \| $																		$ 2,500,000	$ 2,200,000
Employee Stock Purchase Plan [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans																	40,000
Employee Stock Purchase Plan Shares Issued, Intrinsic Value \| $																	$ 1,000,000
Proceeds from Stock Plans \| $																	$ 2,700,000