XML 56 R29.htm IDEA: XBRL DOCUMENT
v3.19.3

Other Real Estate Owned (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2019
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract] |
Summary of Other Real Estate Owned | The following tables set forth activity in OREO for the three and nine months ended September 30, 2019 and 2018:
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2019 |  | 2018 |  | 2019 |  | 2018
|  | (in thousands)
Balance, beginning of period |  | $ | 1,118 |  |  | $ | 7,080 |  |  | $ | 6,019 |  |  | $ | 13,298 |
Transfers in |  | — |  |  | 794 |  |  | 386 |  |  | 1,200 |
Valuation adjustments |  | — |  |  | (495 | ) |  | (195 | ) |  | (697 | )
Proceeds from sale of OREO property |  | (588 | ) |  | (47 | ) |  | (6,382 | ) |  | (5,868 | )
Gain (loss) on sale of OREO, net |  | 95 |  |  | (1 | ) |  | 797 |  |  | (602 | )
Balance, end of period |  | $ | 625 |  |  | $ | 7,331 |  |  | $ | 625 |  |  | $ | 7,331 |

X
- Definition Summary of Other Real Estate Owned [Table Text Block] + References No definition available. + Details
Name: | colb_SummaryofOtherRealEstateOwnedTableTextBlock
Namespace Prefix: | colb_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_OtherRealEstateAndForeclosedAssetsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration