Derivatives and Hedging - Outstanding Derivatives Contracts (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019 USD ($) derivative_instrument outstanding_contract	Dec. 31, 2018 USD ($) outstanding_contract
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	44	142
Notional Amounts	$ 1,603,351	$ 3,027,375
Fair Value Asset (Liability), Net	(80,453)	(12,623)
Unrealized Loss Recorded in AOCI/L	$ (58,369)
Unrealized Loss Recorded in AOCI/L		$ (7,770)
Interest rate swaps
Derivatives, Fair Value [Line Items]
Number of Contracts \| derivative_instrument	4,000,000
Notional Amounts	$ 1,400,000
Designated as hedging instrument \| Other liabilities \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	4	7
Notional Amounts	$ 1,400,000	$ 2,100,000
Fair Value Asset (Liability), Net	(80,233)	(10,681)
Unrealized Loss Recorded in AOCI/L	$ (58,369)
Unrealized Loss Recorded in AOCI/L		$ (7,770)
Not Designated as Hedging Instrument \| Accrued liabilities \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	40	135
Notional Amounts	$ 203,351	$ 927,375
Fair Value Asset (Liability), Net	(220)	(1,942)
Unrealized Loss Recorded in AOCI/L	$ 0
Unrealized Loss Recorded in AOCI/L		$ 0

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Nominal or face amount used to calculate payment on derivative.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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