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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Fair value of all liability derivatives designated as cash flow hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time. Because of their short-term, time deposits are considered 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. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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-Name Accounting Standards Codification
-Topic 210
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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Summary of Significant Accounting Policies - Fair Value Measurements (Details) € in Thousands	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 EUR (€)	Jun. 30, 2018 EUR (€)
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Derivative, amount of hedged item \| €		€ 274,161			€ 179,881
Fair value measured on recurring basis \| Quoted prices in active markets (Level 1)
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Money Market Funds	$ 0
Time Deposits			$ 0
Trading securities	9,744,000		10,248,000
Derivative Assets			0
Interest Rate Swap Agreements Liabilities	0		0
Fair value measured on recurring basis \| Significant other observable inputs (Level 2)
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Money Market Funds	4,418,000
Time Deposits			956,000
Trading securities	622,000		505,000
Derivative Assets			93,000
Interest Rate Swap Agreements Liabilities	8,578,000		973,000
Fair value measured on recurring basis \| Significant unobservable inputs (Level 3)
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Money Market Funds	0
Time Deposits			0
Trading securities	0		0
Derivative Assets			0
Interest Rate Swap Agreements Liabilities	0		0
Estimate of Fair Value Measurement \| Fair value measured on recurring basis
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Money Market Funds	4,418,000
Time Deposits			956,000
Trading securities	10,366,000		10,753,000
Derivative Assets			93,000
Interest Rate Swap Agreements Liabilities	8,578,000		973,000
Designated as Hedging Instrument \| Interest Rate Swap
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Notional amount of derivatives	$ 350,000,000		350,000,000
Long \| Foreign exchange contracts
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Notional amount of derivatives \| €				€ 29,000
Short \| Foreign exchange contracts
Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis [Line Items]
Derivative, amount of hedged item			$ 33,374,000