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Summary of Significant Accounting Policies (Narrative) (Details)					3 Months Ended				9 Months Ended
	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Oct. 31, 2018 USD ($)	Jul. 31, 2018 shares	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($) shares	Jun. 30, 2018 USD ($) Apartment	Mar. 31, 2018 shares	Sep. 30, 2019 USD ($) Apartment shares	Sep. 30, 2018 USD ($) shares
Residential real estate held in other real estate owned	$ 86,000,000	$ 844,000,000			$ 86,000,000				$ 86,000,000
Foreclosure proceedings in process	104,000,000	211,000,000			104,000,000				104,000,000
Total investment in limited partnership	201,000	233,000			201,000				$ 201,000
Number of apartments under the project \| Apartment							37		37
Limited partner capital contribution commitment	7,579,000				7,579,000		$ 7,579,000		$ 7,579,000
Project investment amortization period							10 years		10 years
Annual LIHTCs mount awarded for the project							$ 861,000		$ 861,000
Total anticipated LIHTCs amount under the housing project	8,613,000				8,613,000		$ 8,613,000		8,613,000
Amortization expense					355,000	$ 341,000			$ 1,078,000	$ 837,000
Goodwill, Impairment Loss			$ 0
Dilutive securities impacting in calculation of earnings per share \| shares									0	0
First Priority Financial Corp. [Member]
Goodwill acquired	39,744,000	39,744,000
Stock issued during period, shares \| shares				2,320,800		2,320,800
Scottdale Bank and Trust Company [Member]
Goodwill acquired	19,178,000	19,178,000
Stock issued during period, shares \| shares								1,878,827
Phoenix Bancorp Incorporated [Member]
Goodwill acquired	3,918,000	3,918,000
Core Deposit Intangible [Member]
Intangible assets, net	5,860,000	6,893,000			5,860,000				$ 5,860,000
Amortization expense					338,000	$ 328,000			$ 1,033,000	$ 816,000
Core Deposit Intangible, Amortization Period									10 years
Other Assets [Member]
Total investment in limited partnership	5,810,000	1,710,000			5,810,000				$ 5,810,000
Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and reserves, balance	$ 134,000,000	159,000,000			$ 134,000,000				$ 134,000,000
Maximum [Member]
Non-residential consumer loans charged off on contractual basis in event of bankruptcy, in period	120 days				120 days				120 days
Commercial Portfolio [Member]
Loan terms									1 year
Loan to value ratio	80.00%				80.00%				80.00%
Residential Portfolio [Member] \| Maximum [Member]
Loan terms									30 years
Loan to value ratio	100.00%				100.00%				100.00%
Loan to value ratio, exposure after private mortgage insurance									85.00%
Equity Securities [Member]
Equity securities, fair value	$ 509,000	492,000			$ 509,000				$ 509,000
Equity Securities [Member] \| ASU 2016-01 [Member]
Equity securities, fair value	$ 509,000,000	$ 492,000,000			509,000,000				509,000,000
Equity securities sold					$ 0	$ 0			$ 0	0
Equity Securities [Member] \| ASU 2016-01 [Member] \| Accumulated Other Comprehensive Loss [Member]
Net unrealized losses reclassified										$ 44,000,000
Home equity lines of credit [Member] \| Maximum [Member]
Loan terms									20 years
Loan to value ratio	85.00%				85.00%				85.00%
Home Equity Lines Of Credit [Member] \| Maximum [Member]
Loan terms									5 years