Securities (Narrative) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Jan. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Asset-backed securities pledged to secure certain deposits	$ 47,800,000	$ 41,300,000
Asset-backed securities pledged as collateral	0	3,300,000
Amount	219,942,000	216,247,000
Amortized cost, available for sale	128,922,000	122,524,000
Other-than temporary impairment charges	0	0
Sale of securities	0	0	$ 34,900,000
Securities held to maturity (HTM), at amortized cost	88,654,000	96,271,000
Securities available for sale (AFS), at fair value	131,288,000	119,976,000
Fair value of securities of unrealized losses from amortized cost	24,161,000	84,941,000
Unrealized losses	172,000	2,757,000
Held-to-maturity Securities, Fair Value, Total	90,035,000	93,745,000
Fair value of securities of unrealized losses from amortized cost	27,819,000	83,047,000
Total, unrealized losses	181,000	2,672,000
Gross unrealized losses, available for sale	172,000	2,757,000
Gross unrealized losses, held to maturity	181,000	2,672,000
Residential Mortgage Backed Securities Issued By US Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	11,686,000	7,641,000
Securities held to maturity (HTM), at amortized cost	27,707,000	25,948,000
Securities available for sale (AFS), at fair value	11,792,000	7,361,000
Held-to-maturity Securities, Fair Value, Total	28,592,000	25,267,000
Gross unrealized losses, available for sale	9,000	281,000
Gross unrealized losses, held to maturity	16,000	756,000
Residential Collateralized Mortgage Obligations, Issued By US Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, available for sale	106,038,000	102,411,000
Securities held to maturity (HTM), at amortized cost	47,195,000	52,375,000
Securities available for sale (AFS), at fair value	108,194,000	100,740,000
Held-to-maturity Securities, Fair Value, Total	47,513,000	51,079,000
Gross unrealized losses, available for sale	133,000	1,870,000
Gross unrealized losses, held to maturity	$ 139,000	$ 1,360,000
Asset-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities with unrealized losses, average life	4 years 3 months 27 days	4 years 10 months 17 days
Securities held to maturity (HTM), at amortized cost	$ 27,400,000	$ 82,600,000
Fair value of securities of unrealized losses from amortized cost	24,161,000	84,941,000
Unrealized losses	172,000	2,757,000
Fair value of securities of unrealized losses from amortized cost	25,414,000	77,707,000
Total, unrealized losses	$ 168,000	$ 2,521,000
Asset-backed Securities, Issued by Private Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities with unrealized losses, average life	3 years 9 months 5 days	3 years 4 days
Held to maturity securities with unrealized losses, average duration	3 years 2 months 29 days	2 years 3 months 29 days
Fair value of securities of unrealized losses from amortized cost	$ 399,000	$ 441,000
Total, unrealized losses	13,000	41,000
Us Government Agencies Callable Agency Bonds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities held to maturity (HTM), at amortized cost	2,003,000	5,009,000
Held-to-maturity Securities, Fair Value, Total	2,006,000	4,899,000
Fair value of securities of unrealized losses from amortized cost	2,006,000	4,899,000
Total, unrealized losses	$ 0	110,000
Gross unrealized losses, held to maturity		$ 110,000
Asset Backed Securities Or Bonds Issued By Us Government Sponsored Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Held to maturity securities with unrealized losses, average duration	3 years 4 months 10 days	4 years 3 months 4 days
Fair value of securities of unrealized losses from amortized cost	$ 28,000,000	$ 94,800,000
Total, unrealized losses	$ 200,000	$ 2,700,000
Asset-backed securities issued by GSEs [Member]
Debt and Equity Securities, FV-NI [Line Items]
Available for sale securities, average life	3 years 7 months 8 days	4 years 4 months 13 days
Available for sale securities, average duration	3 years 3 months 19 days	3 years 10 months 10 days
Held to maturity securities, average life	4 years 3 months 27 days	4 years 10 months 17 days
Held to maturity securities, average duration	3 years 10 months 21 days	4 years 3 months
Available for sale securities with unrealized losses, average life	3 years 7 months 23 days	4 years 3 months 26 days
Available for sale securities with unrealized losses, average duration	3 years 4 months 10 days	3 years 9 months 29 days
Securities held to maturity (HTM), at amortized cost	$ 408,000	$ 482,000
Residential Collateralized Mortgage Obligations, Issued By Private Enterprises [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities held to maturity (HTM), at amortized cost	408,000	482,000
Held-to-maturity Securities, Fair Value, Total	399,000	441,000
Gross unrealized losses, held to maturity	13,000	41,000
US Government Obligations [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities held to maturity (HTM), at amortized cost	1,494,000	999,000
Held-to-maturity Securities, Fair Value, Total	$ 1,494,000	998,000
Gross unrealized losses, held to maturity		$ 1,000
Standard Poor's, AAA Rating [Member]
Debt and Equity Securities, FV-NI [Line Items]
Percentage of asset backed securities in investment portfolio	99.00%	99.00%
Amount	$ 219,534,000	$ 215,765,000
Standard Poor's, BB Rating [Member]
Debt and Equity Securities, FV-NI [Line Items]
Amount	$ 0	$ 482,000