Derivative Financial Instruments - Interest Rate Lock Commitments (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Interest Rate Lock Commitments
Derivative Financial Instruments
Unexpired interest rate lock commitments	$ 57.8	$ 69.1

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

No definition available.

Name:	us-gaap_InterestRateDerivativesAtFairValueNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant