Derivatives - Schedule Summarizing Terms of Entity's Derivative Financial Instruments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Derivative [Line Items]
Notional amounts	$ 2,231,162
Cash flow hedging | Swap Agreements | Minimum
Derivative [Line Items]
Notional amounts	$ 4,873
Strike rate	1.13%
Cash flow hedging | Swap Agreements | Maximum
Derivative [Line Items]
Notional amounts	$ 267,431
Strike rate	3.87%