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Trust Preferred Securities (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Trust Preferred Securities Textual [Abstract] |  |
Trust preferred securities, Description | On September 15, 2005, RST II, a wholly-owned subsidiary of the Company, closed a pooled private offering of 10,000 Capital Securities with a liquidation amount of $1,000 per security. The proceeds of the offering were loaned to the Company in exchange for junior subordinated debentures with terms similar to the Capital Securities. Distributions on the Capital Securities are payable quarterly at a variable rate that is based upon the 3-month LIBOR plus 1.80 percent and are included in interest expense in the consolidated financial statements. These securities may be included in Tier 1 capital (with certain limitations applicable) under current regulatory guidelines and interpretations. |
Capital Securities | $ 10.3 | $ 10.3
Capital securities maturity date | Sep. 15, 2035 |

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- Definition The amount of capital securities issued. + References No definition available. + Details
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- Definition Description of trust preferred securities. + References No definition available. + Details
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