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

Contractual rate at which a foreign currency can be purchased or sold.

+ References

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- Definition

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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Derivatives - Schedule of Interest Derivative (Details) € in Thousands, £ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) $ / £	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 GBP (£) $ / £	Dec. 31, 2018 EUR (€) $ / £
Maximum
Derivative [Line Items]
Forward rate \| $ / £	1.29			1.29	1.29
Interest Rate Swap
Derivative [Line Items]
Term of interest rate swap	10 years
Designated Hedges \| Cash flow hedging \| Other gain (loss), net
Derivative [Line Items]
Cash flow hedge ineffectiveness	$ 0	$ 0	$ (401)
Designated Hedges \| Interest Rate Swap \| Three-Month LIBOR
Derivative [Line Items]
Notional amount	0
Designated Hedges \| Interest Rate Cap \| Three-Month LIBOR
Derivative [Line Items]
Notional amount	0
Designated Hedges \| Interest Rate Cap \| One-Month LIBOR
Derivative [Line Items]
Notional amount	0
Designated Hedges \| Interest Rate Cap \| Three-Month Euribor
Derivative [Line Items]
Notional amount \| €					€ 247,513
Designated Hedges \| Interest Rate Cap \| Three-Month GBP LIBOR
Derivative [Line Items]
Notional amount \| £				£ 0
Designated Hedges \| Deliverable swap futures
Derivative [Line Items]
Notional amount	0
Non-Designated Hedges \| Interest rate contracts \| Other gain (loss), net
Derivative [Line Items]
Cash flow hedge ineffectiveness	33,307	$ (15,080)	$ (1,455)
Non-Designated Hedges \| Interest Rate Swap \| Three-Month LIBOR
Derivative [Line Items]
Notional amount	$ 2,000,000
Forward rate	0.0339			0.0339	0.0339
Non-Designated Hedges \| Interest Rate Cap \| Three-Month LIBOR
Derivative [Line Items]
Notional amount	$ 52,155
Forward rate	0.0224			0.0224	0.0224
Non-Designated Hedges \| Interest Rate Cap \| One-Month LIBOR
Derivative [Line Items]
Notional amount	$ 4,009,957
Non-Designated Hedges \| Interest Rate Cap \| One-Month LIBOR \| Minimum
Derivative [Line Items]
Forward rate	0.030			0.030	0.030
Non-Designated Hedges \| Interest Rate Cap \| One-Month LIBOR \| Maximum
Derivative [Line Items]
Forward rate	0.045			0.045	0.045
Non-Designated Hedges \| Interest Rate Cap \| Three-Month Euribor
Derivative [Line Items]
Notional amount \| €					€ 441,151
Non-Designated Hedges \| Interest Rate Cap \| Three-Month Euribor \| Minimum
Derivative [Line Items]
Forward rate	0.008			0.008	0.008
Non-Designated Hedges \| Interest Rate Cap \| Three-Month Euribor \| Maximum
Derivative [Line Items]
Forward rate	0.015			0.015	0.015
Non-Designated Hedges \| Interest Rate Cap \| Three-Month GBP LIBOR
Derivative [Line Items]
Notional amount \| £				£ 363,716
Non-Designated Hedges \| Interest Rate Cap \| Three-Month GBP LIBOR \| Minimum
Derivative [Line Items]
Forward rate	0.015			0.015	0.015
Non-Designated Hedges \| Interest Rate Cap \| Three-Month GBP LIBOR \| Maximum
Derivative [Line Items]
Forward rate	0.025			0.025	0.025
Non-Designated Hedges \| Deliverable swap futures
Derivative [Line Items]
Notional amount	$ 19,000