Loans and Allowance for Losses - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for/(release of) losses	$ 578,000	$ 424,000	$ 314,000	$ (7,000)
Troubled debt restructurings, pre-modification		0		0
Troubled debt restructurings, post-modification	8,300,000		10,600,000	0
Past due financing receivables	28,045,000		28,045,000		$ 26,881,000
Loans subject to removal-of-account provisions	100,000		100,000		100,000
SEC Schedule, 12-09, Allowance, Loan and Lease Loss [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for/(release of) losses	578,000	424,000	314,000	(7,000)
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for/(release of) losses	(158,000)	$ 158,000	(287,000)	$ 179,000
On-balance sheet [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due financing receivables	$ 20,812,000		$ 20,812,000		$ 19,577,000