Derivatives and Hedging - Outstanding Derivatives Contracts (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) derivative_instrument outstanding_contract	Dec. 31, 2017 USD ($) outstanding_contract
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	142	142
Notional Amounts	$ 3,027,375	$ 2,086,764
Fair Value Asset (Liability), Net	(12,623)	3,860
Unrealized Gain (Loss) Recorded in AOCI/L	$ (7,770)	$ 2,483
Interest rate swaps
Derivatives, Fair Value [Line Items]
Number of Contracts \| derivative_instrument	5
Notional Amounts	$ 1,400,000
Other liabilities \| Interest rate swaps \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	7
Notional Amounts	$ 2,100,000
Fair Value Asset (Liability), Net	(10,681)
Unrealized Gain (Loss) Recorded in AOCI/L	$ (7,770)
Other liabilities \| Interest rate swaps \| Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract		5
Notional Amounts		$ 1,400,000
Fair Value Asset (Liability), Net		3,412
Unrealized Gain (Loss) Recorded in AOCI/L		$ 2,483
Accrued liabilities \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	135
Notional Amounts	$ 927,375
Fair Value Asset (Liability), Net	(1,942)
Unrealized Gain (Loss) Recorded in AOCI/L	$ 0
Other current assets \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract		137
Notional Amounts		$ 686,764
Fair Value Asset (Liability), Net		448
Unrealized Gain (Loss) Recorded in AOCI/L		$ 0

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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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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-Name Accounting Standards Codification
-Topic 815
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-Section 50
-Paragraph 1A
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Paragraph 11
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