Securities (Policies)	3 Months Ended
Securities (Policies)	Mar. 31, 2018
Securities [Abstract]
Investment, Policy	Declines in the fair value of HTM securities below their amortized cost, less any current period credit loss, that are deemed to be other-than-temporary are reflected in earnings as realized losses or in other comprehensive income. This classification is dependent upon whether the Company intends to sell the security, or whether it is more likely than not it will be required to sell the security before recovery. The other-than-temporary impairment ("OTTI") shall be recognized in earnings equal to the entire difference between the investment's amortized cost basis and its fair value at the balance sheet date. If the Company does not intend to sell the security and it is not more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis less any current-period credit loss, the OTTI shall be separated into (a) the amount representing the credit loss and (b) the amount related to all other factors. The amount of the total OTTI related to the credit loss shall be recognized in earnings. The amount of the total OTTI related to other factors shall be recognized in other comprehensive income net of applicable taxes. In estimating OTTI losses, management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer and (iii) the historical and implied volatility of the fair value of the security. Management has the intent to hold the securities classified as HTM until they mature, at which time it is believed the Company will receive full value for the securities. The unrealized losses on HTM debt securities are due to increases in market interest rates over yields at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. The fair value is expected to recover as the bonds approach their maturity date or if market yields for such investments decline. Management also has the intent to hold and will not be required to sell, the debt securities classified as AFS for a period of time sufficient for a recovery of cost, which may be until maturity. The unrealized losses on AFS debt securities are due to increases in market interest rates over the yields available at the time the underlying securities were purchased. When necessary, the Company has performed a discounted cash flow analysis to determine whether or not it will receive the contractual principal and interest on certain securities. For AFS debt securities, OTTI losses are recognized in earnings if the Company intends to sell the security. In other cases the Company considers the relevant factors noted above, as well as the Company's intent and ability to retain its investment for a period of time sufficient to allow for any anticipated recovery in market value and whether evidence exists to support a realizable value equal to or greater than the cost basis. Any impairment loss on an equity security is equal to the full difference between the cost basis and the fair value of the security. As of March 31, 2018 and December 31, 2017, management believes the impairments detailed in the table above are temporary. There were no OTTI losses realized in the Company's consolidated statement of income for the quarter ended March 31, 2018. For the quarter ended March 31, 2017, a $1.3 million impairment loss on an equity investment was realized in the Company's consolidated statements of income.

Disclosure of accounting policy for investments in financial assets, including marketable securities (debt and equity securities with readily determinable fair values), investments accounted for under the equity method and cost method, securities borrowed and loaned, and repurchase and resale agreements. For marketable securities, the disclosure may include the entity's accounting treatment for transfers between investment categories and how the fair values for such securities are determined. Also, for all investments, an entity may describe its policy for assessing, recognizing and measuring impairment of the investment.