Loans And Leases (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($) loan
Accounts Notes And Loans Receivable [Line Items]
Loans	$ 406,406	$ 346,125
Loans 90 days or more past due and still accruing interest
Total TDR's	3,386	3,130
Allocated specific reserves to modified TDRs	$ 25	$ 22
Number of loans modified as a TDR \| loan	1	1
TDR's charge-offs	$ 0	$ 0
Number of TDRs in payment default \| loan		1
Cash payments of interest	$ 190	$ 216
Northpointe [Member] \| Mortgage Purchase Program [Member]
Accounts Notes And Loans Receivable [Line Items]
Percent of loans risk rated for capital adequacy	100.00%
Percent of participation agreement interest	95.00%
Ownership interest in each loan is participates	5.00%
Nonaccrual [Member] \| Commitments to Lend Additional Amounts [Member]
Accounts Notes And Loans Receivable [Line Items]
Total TDR's	$ 0	0
Single-Family Mortgage Loans [Member] \| Northpointe [Member] \| Mortgage Purchase Program [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans	37,665	46,919
Other Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Total TDR's	46,731	33,294
Accruing [Member]
Accounts Notes And Loans Receivable [Line Items]
Total TDR's	$ 3,271	$ 2,986
Commercial [Member]
Accounts Notes And Loans Receivable [Line Items]
Number of loans modified as a TDR \| loan	1	1
TDR's charge-offs	$ 841	$ 239

Allocated specific reserves to modified TDRs.

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Loans Participation Agreement Percentage

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- Definition

Ownership Interest In Each Loan

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- Definition

Percent Of Loans Held Risk Rated For Capital Adequacy

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Number of financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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-Publisher FASB
-Name Accounting Standards Codification
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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

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-Publisher FASB
-Name Accounting Standards Codification
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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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-Publisher FASB
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Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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