Loans Loans - Revolving Loans Converted to Term (Details) - Revolving Loans Converted to Term [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	$ 47,520	$ 81,038
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	9,405	18,975
Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	26,839	42,186
Commercial Real Estate Buildings Land And Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	0	7,551
Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	0	0
Total consumer real estate loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	905	1,955
Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining Revolving Loans Converted to Term During Period	$ 10,371	$ 10,371