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Summary of Significant Accounting Policies (Narrative) (Details)				3 Months Ended			6 Months Ended
	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Oct. 31, 2018 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2018 USD ($) Apartment shares	Mar. 31, 2018 USD ($) shares	Jun. 30, 2018 USD ($) Apartment
Residential real estate held in other real estate owned	$ 350,000,000	$ 844,000,000		$ 350,000,000
Foreclosure proceedings in process	213,000,000	211,000,000		213,000,000
Total investment in limited partnership	222,000	233,000		222,000
Number of apartments under the project \| Apartment					37		37
Limited partner capital contribution commitment					$ 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
Amortization expense				363,000		$ 248,000
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
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	6,544,000	6,893,000		6,544,000
Amortization expense				$ 348,000		$ 245,000
Core Deposit Intangible, Amortization Period				10 years
Other Assets [Member]
Total investment in limited partnership	2,744,000	1,710,000		$ 2,744,000
Reserve for Off-balance Sheet Activities [Member]
Valuation allowances and reserves, balance	$ 135,000,000	159,000,000		$ 135,000,000
Maximum [Member]
Non-residential consumer loans charged off on contractual basis in event of bankruptcy, in period				120 days
Commercial Portfolio [Member]
Loan terms				1 year
Loan to value ratio	80.00%			80.00%
Residential Portfolio [Member] \| Maximum [Member]
Loan terms				30 years
Loan to value ratio	100.00%			100.00%
Loan to value ratio, exposure after private mortgage insurance				85.00%
Equity Securities [Member]
Equity securities, fair value	$ 498,000	492,000		$ 498,000
Equity Securities [Member] \| ASU 2016-01 [Member]
Equity securities, fair value	$ 498,000,000	$ 492,000,000		498,000,000
Equity securities sold				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%
Home Equity Lines Of Credit [Member] \| Maximum [Member]
Loan terms				5 years