Commitments and Contingencies (Financial Instruments with Off Balance Sheet Risk) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 89,682	$ 30,766
Forward sale commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	149,404	61,993
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	678,865	648,050
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	678,865	648,050
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	46,205	46,510
Foreign exchange contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	2,763	2,784
Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	60,000	60,000
Commitments to extend credit on commerical loans [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	480,851	533,884
Commitments to extend credit on home equity lines [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	285,601	270,462
Commitments to extend credit on other loans [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	87,343	46,698
Commitments to extend credit on standby letters of credit [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	$ 9,189	$ 7,706