XML 33 R40.htm IDEA: XBRL DOCUMENT v2.4.0.8

Common Stock Dividend (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended				9 Months Ended				0 Months Ended
	Jun. 24, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 23, 2014	Jun. 24, 2014	Oct. 22, 2014 Subsequent Event [Member]
Subsequent Event [Line Items]
Additional number of shares issued to shareholders (in shares)			149,448	147,946						151,178
Common stock dividend declared	1.00%		1.00%	1.00%
Amount transferred from retained earnings to common stocks based on closing price on declaration date			$ 831	$ 854				$ 839
Closing price of common stock on declaration date (in dollars per share)									$ 5.55
Percentage of stock dividend declared on common stocks outstanding (in hundredths)		1.00%			1.00%	1.00%	1.00%

X

- Definition

This element represents value of shares transferred from retained earning to common stock based on closing price on declaration date.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

X

- Definition

Closing price per share amount for each share of common stock offered in the stock market on declaration date.

+ References

No definition available.

+ Details

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Period Type:	instant

X

- Definition

Common Stock, Dividend Rate, Declared

+ References

No definition available.

+ Details

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Namespace Prefix:	ubfo_
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Period Type:	duration

X

- Definition

Percentage of stock dividends for common shareholders declared by an entity during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	ubfo_
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X

- Definition

Number of shares issued for noncash consideration for development stage entities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 915

-SubTopic 215

-Section 45

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6472370&loc=d3e38297-110927

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- Details

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