Loans and Leases - Outstanding Principal Balance and Related Carrying Amount of Loans Acquired in VIST Acquisition (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Total Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding principal balance	$ 3,652	$ 3,604
Carrying amount	3,438	3,471
VIST | Acquired Credit Impaired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding principal balance	12,822	14,337
Carrying amount	11,036	11,962
VIST | Acquired Non-Credit Impaired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding principal balance	256,265	301,128
Carrying amount	254,162	298,615
VIST | Total Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding principal balance	269,087	315,465
Carrying amount	$ 265,198	$ 310,577