Derivative Financial Instruments (Location and Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Derivatives not designated as hedging instruments, fair value
Fair value of asset derivatives	$ 26,104	$ 49,377
Fair value of liability derivatives	26,104	49,377
Effective portion of interest rate cash flow hedge, fair value included in accumulated other comprehensive income	3,461	5,550
Interest Rate Cash Flow Hedge Liability at Fair Value	$ 3,461	$ 5,550
Other Assets
Derivatives not designated as hedging instruments, fair value
Description of location of interest rate derivative instruments not designated as hedging instruments on balance sheet	Derivatives	Derivatives
Other Liabilities
Derivatives not designated as hedging instruments, fair value
Description of location of interest rate derivative instruments not designated as hedging instruments on balance sheet	Derivatives	Derivatives
Description of location of interest rate derivatives designated as hedging instruments on the balance sheet	Derivatives	Derivatives
Accumulated other comprehensive income
Derivatives not designated as hedging instruments, fair value
Description of location of interest rate derivatives designated as hedging instruments on the balance sheet	Accumulated other comprehensive income (1)	Accumulated other comprehensive income (1)

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