Derivatives and Hedging Activities - Schedule of Derivatives in Statement of Financial Position, Fair Value (Details) - Swap - Significant Other Observable Inputs Level 2 - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	$ (16,987)	$ (6,008)
Designated as Hedging Instrument | Interest rate swaps, net | USD | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	(6,127)	(939)
Designated as Hedging Instrument | Interest rate swaps, net | GBP | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	(8,836)	(4,524)
Designated as Hedging Instrument | Interest rate swaps, net | GBP | Derivatives assets, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	0	366
Designated as Hedging Instrument | Interest rate swaps, net | EUR | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	(2,024)	(1,139)
Designated as Hedging Instrument | Interest rate swaps, net | EUR | Derivatives assets, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	0	228
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	3,485	2,652
Not Designated as Hedging Instrument | Interest rate swaps, net | EUR | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	0	(74)
Not Designated as Hedging Instrument | Foreign currency forwards | GBP | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	(378)	(831)
Not Designated as Hedging Instrument | Foreign currency forwards | GBP | Derivatives assets, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	2,114	1,205
Not Designated as Hedging Instrument | Foreign currency forwards | EUR | Derivatives liabilities, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	(177)	0
Not Designated as Hedging Instrument | Foreign currency forwards | EUR | Derivatives assets, at fair value
Derivatives, Fair Value [Line Items]
Derivatives, at fair value	$ 1,926	$ 2,352