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Accumulated Other Comprehensive Income | 9 Months Ended
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Sep. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Abstract] |
Accumulated Other Comprehensive Income | Accumulated Other Comprehensive Loss The following table shows changes in accumulated other comprehensive income (loss) by component for the three and nine month periods ended September 30, 2017 and 2016:
|  | Unrealized Gains and Losses on Available-for-Sale Securities (1) |  | Unrealized Gains and Losses on Pension Plan Liability (1) |  | Total (1)
Three months ended September 30, 2017 |  | (in thousands)
Beginning balance |  | $ | (4,969 | ) |  | $ | (1,559 | ) |  | $ | (6,528 | )
Other comprehensive income before reclassifications |  | 549 |  |  | — |  |  | 549 |
Amounts reclassified from accumulated other comprehensive income |  | — |  |  | 46 |  |  | 46 |
Net current-period other comprehensive income |  | 549 |  |  | 46 |  |  | 595 |
Ending balance |  | $ | (4,420 | ) |  | $ | (1,513 | ) |  | $ | (5,933 | )
Three months ended September 30, 2016 |  |  |  |  |  |
Beginning balance |  | $ | 27,280 |  |  | $ | (6,469 | ) |  | $ | 20,811 |
Other comprehensive loss before reclassifications |  | (4,049 | ) |  | — |  |  | (4,049 | )
Amounts reclassified from accumulated other comprehensive income (loss) |  | (364 | ) |  | 107 |  |  | (257 | )
Net current-period other comprehensive income (loss) |  | (4,413 | ) |  | 107 |  |  | (4,306 | )
Ending balance |  | $ | 22,867 |  |  | $ | (6,362 | ) |  | $ | 16,505 |
Nine months ended September 30, 2017 |  |  |  |  |  |
Beginning balance |  | $ | (12,704 | ) |  | $ | (6,295 | ) |  | $ | (18,999 | )
Other comprehensive income before reclassifications |  | 8,284 |  |  | 4,604 |  |  | 12,888 |
Amounts reclassified from accumulated other comprehensive income |  | — |  |  | 178 |  |  | 178 |
Net current-period other comprehensive income |  | 8,284 |  |  | 4,782 |  |  | 13,066 |
Ending balance |  | $ | (4,420 | ) |  | $ | (1,513 | ) |  | $ | (5,933 | )
Nine months ended September 30, 2016 |  |  |  |  |  |
Beginning balance |  | $ | 386 |  |  | $ | (6,681 | ) |  | $ | (6,295 | )
Other comprehensive income before reclassifications |  | 23,229 |  |  | — |  |  | 23,229 |
Amounts reclassified from accumulated other comprehensive income (loss) |  | (748 | ) |  | 319 |  |  | (429 | )
Net current-period other comprehensive income |  | 22,481 |  |  | 319 |  |  | 22,800 |
Ending balance |  | $ | 22,867 |  |  | $ | (6,362 | ) |  | $ | 16,505 |
__________ (1) All amounts are net of tax. Amounts in parenthesis indicate debits. The following table shows details regarding the reclassifications from accumulated other comprehensive income (loss) for the three and nine month periods ended September 30, 2017 and 2016:
|  | Amount Reclassified from Accumulated Other Comprehensive Income (Loss) |  |
|  | Three Months Ended September 30, |  | Nine Months Ended September 30, |  | Affected line Item in the Consolidated
|  | 2017 |  | 2016 |  | 2017 |  | 2016 |  | Statement of Income
|  | (in thousands) |  |
Unrealized gains and losses on available-for-sale securities |  |  |  |  |  |  |  |  |  |
Investment securities gains |  | $ | — |  |  | $ | 572 |  |  | $ | — |  |  | $ | 1,174 |  |  | Investment securities gains, net
|  | — |  |  | 572 |  |  | — |  |  | 1,174 |  |  | Total before tax
|  | — |  |  | (208 | ) |  | — |  |  | (426 | ) |  | Income tax provision
|  | $ | — |  |  | $ | 364 |  |  | $ | — |  |  | $ | 748 |  |  | Net of tax
Amortization of pension plan liability |  |  |  |  |  |  |  |  |  |
Actuarial losses |  | $ | (72 | ) |  | $ | (167 | ) |  | $ | (279 | ) |  | $ | (501 | ) |  | Compensation and employee benefits
|  | (72 | ) |  | (167 | ) |  | (279 | ) |  | (501 | ) |  | Total before tax
|  | 26 |  |  | 60 |  |  | 101 |  |  | 182 |  |  | Income tax benefit
|  | $ | (46 | ) |  | $ | (107 | ) |  | $ | (178 | ) |  | $ | (319 | ) |  | Net of tax

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- Definition Accumulated Other Comprehensive Income (Loss) [Abstract] + References No definition available. + Details
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- Definition Accumulated Other Comprehensive Income (Loss) + References No definition available. + Details
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Namespace Prefix: | colb_
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