Loans (Details 6) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of information pertaining to impaired loans
Impaired loans without a valuation allowance	$ 9,021	$ 9,303	$ 3,410
Impaired loans with a valuation allowance	10,127	6,472	9,029
Total impaired loans before valuation allowances	19,148	15,775	12,439
Valuation allowance related to impaired loans	2,258	2,108	2,434
Net impaired loans	16,890psbq_NetImpairedLoans	13,667psbq_NetImpairedLoans	10,005psbq_NetImpairedLoans
Average recorded investment, net of allowance for loan losses	17,465	14,109	12,026
Interest income recognized	586	534	569
Interest income recognized on a cash basis on impaired loans	$ 0	$ 0	$ 0

Net loans deemed to be impaired after application of the allowance.

No definition available.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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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.

+ References

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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