Additional income tax.

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The amortization period of certain tax benefits including purchased know-how and patents.

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Years subject to audit by income tax authorities, in CCYY format.

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New Federal corporate tax rate for periods beginning on or after January 1, 2018.

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Operating loss carryforwards have no expiration date

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Amount of other deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. For example, but not limited to, acquisition-date income tax benefits or expenses recognized from changes in the acquirer's valuation allowance for its previously existing deferred tax assets resulting from a business combination and adjustments to beginning-of-year balance of a valuation allowance because of a change in circumstance causing a change in judgment about the realizability of the related deferred tax asset in future periods.

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Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of foreign subsidiaries.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year being audited in the income tax examination, in CCYY format.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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TAXES ON INCOME (Narrative) (Details) $ in Thousands	12 Months Ended
TAXES ON INCOME (Narrative) (Details) $ in Thousands	Dec. 31, 2018 USD ($) Integer	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Tax rate	23.00%	24.00%	25.00%
Effective tax rate	14.70%	(10.50%)	14.80%
Income tax expense	$ 27,377	$ (13,631)	$ 21,412
Income taxes paid	42,858	33,029	$ 28,396
Tax loss carry-forwards	375,786
Tax loss carry-forwards that have no expiration date	$ 71,345
Operating loss carry-forwards expiration date	Dec. 31, 2038
Accrued interest related to income tax uncertainties	$ 501	1,262
Deferred tax benefit		$ 30,923
New Federal corporate tax rate for periods beginning on or after January 1, 2018		21.00%
Additional income tax	2,975
Net operating losses expense	$ 4,786
Minimum [Member] \| Other Income Tax Authority [Member]
Year subject to audit	2011
Maximum [Member] \| Other Income Tax Authority [Member]
Year subject to audit	2017
Tax Year 2010 [Member] \| Israel Tax Authority [Member]
Settlement of tax year under examination	2011
Earliest Tax Year [Member]
Operating loss carry-forwards expiration date	Dec. 31, 2019
Latest Tax Year [Member]
Operating loss carry-forwards expiration date	Dec. 31, 2038
Tax Year 2013 [Member] \| Israel Tax Authority [Member]
Year under examination	2013
Settlement of tax year under examination	2016
United Kingdom [Member]
Tax rate	19.00%
United States [Member]
Tax rate	25.00%
Encouragement of Industry [Member]
Number of annual installments for dedcution of public offering expenses \| Integer	3
Amortization period of purchased know-how and patents	8 years
Non-Israeli Subsidiaries [Member]
Undistributed earnings	$ 489,123
Unrecognized deferred tax liability	$ 79,658
From 2015 through 2016 [Member] \| The election [Member]
Tax rate	16.00%
2017 and thereafter [Member] \| The election [Member]
Tax rate	12.00%
2017 [Member] \| Income not eligible for Preferred Enterprise benefits [Member]
Tax rate			24.00%
2018 and thereafter [Member] \| Income not eligible for Preferred Enterprise benefits [Member]
Tax rate	23.00%
2012 [Member]
Tax rate	20.00%