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Subordinated Debentures (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Terms of Subordinated Debentures |  |
Balance | $ 126,135 | $ 125,991
First Company Statutory Trust 2001 |  |
Terms of Subordinated Debentures |  |
Balance | $ 3,269 |
Rate at December 31, 2017 | 4.68% |
Variable Rate Structure | 3 month LIBOR plus 3.30% |
LIBOR Rate Spread | 3.30% |
Maturity Date | Jul. 31, 2031 |
First Company Statutory Trust 2003 |  |
Terms of Subordinated Debentures |  |
Balance | $ 2,407 |
Rate at December 31, 2017 | 4.925% |
Variable Rate Structure | 3 month LIBOR plus 3.25% |
LIBOR Rate Spread | 3.25% |
Maturity Date | Mar. 26, 2033 |
Glacier Capital Trust II |  |
Terms of Subordinated Debentures |  |
Balance | $ 46,393 |
Rate at December 31, 2017 | 4.109% |
Variable Rate Structure | 3 month LIBOR plus 2.75% |
LIBOR Rate Spread | 2.75% |
Maturity Date | Apr. 07, 2034 |
Citizens (ID) Statutory Trust I |  |
Terms of Subordinated Debentures |  |
Balance | $ 5,155 |
Rate at December 31, 2017 | 4.25% |
Variable Rate Structure | 3 month LIBOR plus 2.65% |
LIBOR Rate Spread | 2.65% |
Maturity Date | Jun. 17, 2034 |
Glacier Capital Trust III |  |
Terms of Subordinated Debentures |  |
Balance | $ 36,083 |
Rate at December 31, 2017 | 2.649% |
Variable Rate Structure | 3 month LIBOR plus 1.29% |
LIBOR Rate Spread | 1.29% |
Maturity Date | Apr. 07, 2036 |
Glacier Capital Trust IV |  |
Terms of Subordinated Debentures |  |
Balance | $ 30,928 |
Rate at December 31, 2017 | 3.158% |
Variable Rate Structure | 3 month LIBOR plus 1.57% |
LIBOR Rate Spread | 1.57% |
Maturity Date | Sep. 15, 2036 |
Bank of the San Juans Bancorporation Trust I |  |
Terms of Subordinated Debentures |  |
Balance | $ 1,900 |
Rate at December 31, 2017 | 3.301% |
Variable Rate Structure | 3 month LIBOR plus 1.82% |
LIBOR Rate Spread | 1.82% |
Maturity Date | Mar. 01, 2037 |

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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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