Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2017
Accounting Policies [Abstract]
Business and Consolidation	Basis of Financial Statement Presentation The condensed consolidated financial statements of the Company and its subsidiaries have been prepared in accordance with the accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The condensed consolidated financial statements include the accounts of the Company and its subsidiaries, all of which are wholly owned. All intercompany accounts and transactions have been eliminated. In 2017, the Company changed its presentation of loans on the face of the Condensed Consolidated Balance Sheets to combine originated loans with purchased loans. See Note 5 - Loans for more information. The Company adopted Accounting Standards Update (ASU) 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting during the first quarter of 2017. Among other elements, the ASU requires an entity to recognize all excess tax benefits and deficiencies related to stock-based compensation expense as income tax expense or benefit in the statements of operations. The ASU requires adjustments be reflected as of the beginning of the fiscal year of adoption and as a result, $5.2 million of previously recognized excess tax benefits were reclassified from Additional paid in capital to Retained earnings during the first quarter of 2017. The adoption resulted in a decrease to income tax expense of $1.3 million for the three months ended March 31, 2017. Excess tax benefits related to stock compensation are presented as a cash inflow from operating activities for the three months ended March 31, 2017 due to the prospective adoption of employee share-based payment guidance in 2017. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Acquisitions Acquisitions and business combinations are accounted for using the acquisition method of accounting. The assets and liabilities of the acquired entities have been recorded at their estimated fair values at the date of acquisition. Goodwill represents the excess of the purchase price over the fair value of net assets acquired, including the amount assigned to indentifiable intangible assets. The purchase price allocation process requires an estimation of the fair values of the assets acquired and the liabilities assumed. When a business combination agreement provides for an adjustment to the cost of the combination contingent on future events, the Company includes an estimate of the acquisition-date fair value as part of the cost of the combination. To determine the fair values, the Company relies on third party valuations, such as appraisals, or internal valuations based on discounted cash flow analyses or other valuation techniques. The results of operations of the acquired business are included in the Company's consolidated financial statements from the date of acquisition. Merger-related costs are costs the Company incurs to effect a business combination. In 2017, the Company changed its presentation of Merger related expenses as a separate component of Noninterest expenses on the Condensed Consolidated Statements of Operations. Merger related expenses include costs directly related to merger or acquisition activity and include legal and professional fees, system consolidation and conversion costs, and compensation costs such as severance and retention incentives for employees impacted by acquisition activity. The Company accounts for merger-related costs as expenses in the periods in which the costs are incurred and the services are received.
Available-for-sale Securities	Management systematically evaluates investment securities for other-than-temporary declines in fair value on a quarterly basis. This analysis requires management to consider various factors, which include among other considerations (1) the present value of the cash flows expected to be collected compared to the amortized cost of the security, (2) duration and magnitude of the decline in value, (3) the financial condition of the issuer or issuers, (4) structure of the security, and (5) the intent to sell the security or whether it is more likely than not the Company would be required to sell the security before its anticipated recovery in market value. At March 31, 2017, management performed its quarterly analysis of all securities with an unrealized loss and concluded no individual securities were other-than-temporarily impaired.