Premises and Equipment (Lease Commitments, Components of Lease Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Amortization of lease right-of-use assets	$ 32,772	$ 27,626
Short-term lease expense	1,799	4,592
Non-lease components (including taxes, insurance, common maintenance, etc.)	11,396	9,896
Total operating lease expense, excluding rent	$ 45,967	$ 42,114