Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Topic 835
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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- Definition

Current period adjustment in other comprehensive income reflecting gains or losses on foreign currency transactions that are designated as, and are effective as, hedges of a net investment in a foreign entity, net of tax effect.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (b)
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Derivative Instruments, Hedging Activities and Fair Value (Details 3) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2022	Dec. 31, 2018	Dec. 31, 2017
Foreign Currency Derivatives
Pre-tax net gains (losses) on certain loans designated as hedges of net investments in foreign subsidiaries	$ 9,500	$ 1,900
Foreign currency forward exchange contracts
Foreign Currency Derivatives
U.S. Dollar Equivalent	647,982				$ 671,857
Recognized Gain (Loss)	(3,944)	(1,879)
Foreign currency forward exchange contracts \| British pounds sterling \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	77,579				76,761
Recognized Gain (Loss)	(202)	(769)
Foreign currency forward exchange contracts \| British pounds sterling \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	10,789				5,960
Recognized Gain (Loss)	134	72
Foreign currency forward exchange contracts \| Euros \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	311,405				314,649
Recognized Gain (Loss)	(6,322)	(4,916)
Foreign currency forward exchange contracts \| Euros \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	203,648				223,111
Recognized Gain (Loss)	3,613	4,564
Foreign currency forward exchange contracts \| Other currencies \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	41,660				39,889
Recognized Gain (Loss)	(1,148)	(1,049)
Foreign currency forward exchange contracts \| Other currencies \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	2,901				$ 11,487
Recognized Gain (Loss)	(19)	$ 219
Term Loan Facility, Fixed-Rate \| Term Loan
Foreign Currency Derivatives
Principal amount	$ 300,000
LIBOR \| Scenario, Forecast \| Term Loan Facility, Fixed-Rate \| Term Loan
Foreign Currency Derivatives
Debt Instrument, Basis Spread on Variable Rate			3.12%	1.65%