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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 835
-SubTopic 30
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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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-Name Accounting Standards Codification
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- Definition

The cash inflow from a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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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.

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Derivative Instruments, Hedging Activities and Fair Value (Details 3) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2021	Dec. 31, 2018	Jan. 31, 2017	Dec. 31, 2016
Foreign Currency Derivatives
Pre-tax net gains (losses) on certain loans designated as hedges of net investments in foreign subsidiaries	$ 7,700	$ (16,400)	$ 9,500	$ (20,300)
Proceeds from cross-currency interest rate swap termination			0	16,625
Foreign currency forward exchange contracts
Foreign Currency Derivatives
U.S. Dollar Equivalent	608,241		608,241					$ 600,883
Recognized Gain (Loss)			(13,985)	1,394
Foreign currency forward exchange contracts \| British pounds sterling \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	69,228		69,228					55,120
Recognized Gain (Loss)			(1,516)	(228)
Foreign currency forward exchange contracts \| British pounds sterling \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	9,788		9,788					827
Recognized Gain (Loss)			108	(14)
Foreign currency forward exchange contracts \| Euros \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	304,566		304,566					326,797
Recognized Gain (Loss)			(14,233)	628
Foreign currency forward exchange contracts \| Euros \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	163,183		163,183					171,578
Recognized Gain (Loss)			2,482	(468)
Foreign currency forward exchange contracts \| Other currencies \| Sell
Foreign Currency Derivatives
U.S. Dollar Equivalent	47,184		47,184					43,455
Recognized Gain (Loss)			(880)	1,477
Foreign currency forward exchange contracts \| Other currencies \| Buy
Foreign Currency Derivatives
U.S. Dollar Equivalent	$ 14,292		14,292					$ 3,106
Recognized Gain (Loss)			$ 54	$ (1)
Term Loan Facility, Fixed-Rate \| Term Loan
Foreign Currency Derivatives
Principal amount							$ 300,000
LIBOR \| Scenario, Forecast \| Term Loan Facility, Fixed-Rate \| Subsequent Event \| Term Loan
Foreign Currency Derivatives
Debt Instrument, Basis Spread on Variable Rate					2.71%	1.65%