Derivative Instruments and Hedging Activities (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized gain fair value	$ 325
Not Designated as Hedging Instrument [Member] \| Floating interest rate swaps [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	13,646	14,323
Receive fixed rate (average)	2.00%	2.00%
Pay variable rate (average)	0.16%	0.17%
Maturity, Lower maturity range	2015-03-31	2015-03-31
Maturity, Higher maturity range	2021-10-31	2021-10-31
Weighted average remaining term	1 year 10 months 24 days	2 years 10 months 24 days
Unrealized gain fair value	$ 194	$ 276

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Latest Maturity Date of derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	psbq_
Data Type:	xbrli:dateTimeItemType
Balance Type:	na
Period Type:	duration

- Definition

Earliest Maturity Date of derivatives.

+ References

No definition available.

+ Details

Name:	psbq_DerivativeMaturityDateLowEnd
Namespace Prefix:	psbq_
Data Type:	xbrli:dateTimeItemType
Balance Type:	na
Period Type:	duration

- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeAverageFixedInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeAverageVariableInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (a),(c),(d),(e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

+ Details

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Balance Type:	credit
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- Details

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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