PCI Loans and Related Allowance for Loan Losses (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Jan. 30, 2009
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased credit impaired (PCI) loans	$ 36,803	$ 38,285
Covered Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased credit impaired (PCI) loans			$ 198,300
Loans met criteria of ASC 310-30			49,100
Outstanding contractual balance of covered loans	$ 59,800	$ 62,200
Covered Loans [Member] | Residential 1-4 Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Remaining of loans acquired			$ 149,100