v2.4.0.6

Regulatory Capital Requirements (Tables) | 12 Months Ended
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Dec. 31, 2011
Regulatory Capital Requirements [Abstract] |
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations | As of December 31, 2011, the most recent notification from the Federal Deposit Insurance Corporation categorized Columbia Bank as well capitalized under the regulatory framework for prompt corrective action. To be categorized as well capitalized, an institution must maintain minimum total risk-based, Tier 1 risk-based, and Tier 1 leverage ratios as set forth in the following tables. There are no conditions or events since the notification that management believes have changed Columbia Bank’s category. The Company and its banking subsidiary’s actual capital amounts and ratios as of December 31, 2011 and 2010, are also presented in the following table.
|  | Actual |  | For Capital Adequacy Purposes |  | To Be Well Capitalized Under Prompt Corrective Action Provision
Amount |  | Ratio |  | Amount |  | Ratio |  | Amount |  | Ratio
|  | (dollars in thousands)
As of December 31, 2011 |  |  |  |  |  |  |  |  |  |  |  |
Total Capital (to risk-weighted assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 636,559 |  |  | 21.05 | % |  | $ | 241,955 |  |  | 8.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 561,216 |  |  | 18.55 | % |  | $ | 242,028 |  |  | 8.0 | % |  | $ | 302,535 |  |  | 10.0 | %
Tier 1 Capital (to risk-weighted assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 598,485 |  |  | 19.79 | % |  | $ | 120,978 |  |  | 4.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 523,131 |  |  | 17.29 | % |  | $ | 121,014 |  |  | 4.0 | % |  | $ | 181,521 |  |  | 6.0 | %
Tier 1 Capital (to average assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 598,485 |  |  | 12.96 | % |  | $ | 184,780 |  |  | 4.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 523,131 |  |  | 11.45 | % |  | $ | 182,747 |  |  | 4.0 | % |  | $ | 228,434 |  |  | 5.0 | %
As of December 31, 2010 |  |  |  |  |  |  |  |  |  |  |  |
Total Capital (to risk-weighted assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 623,526 |  |  | 24.47 | % |  | $ | 203,871 |  |  | 8.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 463,587 |  |  | 18.20 | % |  | $ | 203,789 |  |  | 8.0 | % |  | $ | 254,736 |  |  | 10.0 | %
Tier 1 Capital (to risk-weighted assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 591,263 |  |  | 23.20 | % |  | $ | 101,936 |  |  | 4.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 431,337 |  |  | 16.93 | % |  | $ | 101,894 |  |  | 4.0 | % |  | $ | 152,841 |  |  | 6.0 | %
Tier 1 Capital (to average assets): |  |  |  |  |  |  |  |  |  |  |  |
The Company |  | $ | 591,263 |  |  | 13.99 | % |  | $ | 169,062 |  |  | 4.0 | % |  | N/A |  |  | N/A |
Columbia Bank |  | $ | 431,337 |  |  | 10.33 | % |  | $ | 166,961 |  |  | 4.0 | % |  | $ | 208,702 |  |  | 5.0 | %

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- Definition Tabular disclosure of the capital amounts and ratios as of the balance sheet date, indicating whether the entity or entities are in compliance with regulatory capital requirements, by entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=6918689&loc=SL5958570-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1G -URI http://asc.fasb.org/extlink&oid=6918689&loc=SL5958577-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Chapter 17 -Paragraph 18 -IssueDate 2006-05-01 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -URI http://asc.fasb.org/extlink&oid=6918689&loc=d3e65071-112826 -Subparagraph (c)(2) Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6918689&loc=SL5958568-112826 + Details
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