ACCOUNTING POLICIES (Policies)	9 Months Ended
ACCOUNTING POLICIES (Policies)	Sep. 30, 2018
Accounting Policies [Abstract]
Business Combinations	Business Combinations and Divestitures On January 1, 2018, the Company completed the acquisition of Xenith, a bank holding company based in Richmond, Virginia. On April 1, 2018, the Bank completed its acquisition of DHFB, a Roanoke, Virginia-based investment advisory firm with approximately $600 million in assets under management and advisement at the time of acquisition. DHFB operates as a subsidiary of the Bank. On July 1, 2018, ODCM, a subsidiary of the Bank completed its acquisition of OAL, a McLean, Virginia-based investment advisory firm with approximately $400 million in assets under management and advisement at the time of acquisition. OAL operates as a subsidiary of ODCM. These transactions were accounted for using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed, and consideration exchanged were recorded at estimated fair values on the acquisition date. Fair values are preliminary and subject to refinement for up to one year after the closing date of the acquisition. The resulting goodwill from these transactions is not deductible for tax purposes. Refer to Note 2 “Acquisitions" for further discussion on the Company's business combinations during the period.
Divestitures	On May 23, 2018, the Bank announced that it had entered into an agreement with a third party mortgage company, TFSB, to allow TFSB to offer residential mortgages from certain Bank locations on the terms and conditions set forth in the agreement. Concurrently with this arrangement, the Bank began the process of winding down the operations of UMG, the Company's reportable mortgage segment. Refer to Note 13 "Segment Reporting & Discontinued Operations" for further discussion of this agreement. On June 29, 2018, the Bank entered into an agreement to sell substantially all of the assets and certain specific liabilities of Shore Premier, consisting primarily of marine loans totaling approximately $383.9 million, for a purchase price consisting of approximately $375.0 million in cash and 1,250,000 shares of the purchasing company's common stock. The purchasing company has agreed for a period of 30 days to pay additional cash consideration to the Company to the extent any sales of its common stock by the Company, following satisfaction of any required holding periods or other requirements under the Securities Act, are at prices lower than the agreed upon value at the time of entry into the agreement. The fair value of the purchasing company's common stock is evaluated quarterly and amounts that fall below the original purchase price are recorded as miscellaneous receivable on the Company's Consolidated Balance Sheets. At September 30, 2018, the fair value of the purchasing company's common stock was $27.4 million, which was included as "Marketable Equity Securities" in the Company's Consolidated Balance Sheet. The purchase of the loans was completed on June 29, 2018 and became effective at the end of the day on June 30, 2018. The sale generated an after-tax gain of approximately $15.8 million, net of transaction and other related costs. Refer to Note 3 "Securities" and Note 8 "Derivatives" for further discussion on the Shore Premier sale. On June 29, 2018, the Bank sold approximately $206.3 million in consumer home improvement loans that had been originated through a third-party lending program. These loans were sold at par.
Affordable Housing Entities	Affordable Housing Entities The Company invests in private investment funds that make equity investments in multifamily affordable housing properties that provide affordable housing tax credits for these investments. The activities of these entities are financed with a combination of invested equity capital and debt.
Reclassifications	Reclassifications The accompanying unaudited consolidated financial statements and notes reflect reclassification of certain prior period amounts to conform to the current period presentation. The Company historically presented former bank premises and foreclosed properties as OREO; however,
Adoption of New Accounting Standards and Recent Accounting Pronouncements	Adoption of New Accounting Standards On January 1, 2018, the Company adopted ASU No. 2014-09, “Revenue from Contracts with Customers: Topic 606” and all subsequent amendments to the ASU No. 2014-09 (“Topic 606”). This ASU revised guidance for the recognition, measurement, and disclosure of revenue from contracts with customers. The guidance, as amended, is applicable to all entities and replaces a significant portion of existing industry and transaction-specific revenue recognition rules with a more principles-based recognition model. Most revenue associated with financial instruments, including interest income, loan origination fees, and credit card fees, is outside the scope of the guidance. Gains and losses on investment securities, derivatives, and sales of financial instruments are similarly excluded from the scope. The Company adopted this ASU using the modified retrospective approach, which requires a cumulative effect adjustment to retained earnings as of the beginning of the reporting period in which the entity first applies the new guidance. The adoption of Topic 606 did not have a material impact on the Company’s consolidated financial results but did result in expanded disclosures related to noninterest income and enhanced qualitative disclosures on the revenues within the scope of the new guidance. Refer to Note 11 “Revenue" for further discussion on the Company's accounting policies for revenue sources within the scope of Topic 606. On January 1, 2018, the Company adopted ASU No. 2016-01, “Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities.” This ASU requires an entity to, among other things: (i) measure equity investments at fair value through net income, with certain exceptions; (ii) present in OCI the changes in instrument-specific credit risk for financial liabilities measured using the fair value option; (iii) present financial assets and financial liabilities by measurement category and form of financial asset; (iv) calculate the fair value of financial instruments for disclosure purposes based on an exit price and; (v) assess a valuation allowance on deferred tax assets related to unrealized losses of AFS debt securities in combination with other deferred tax assets. This ASU provides an election to subsequently measure certain nonmarketable equity investments at cost less any impairment and adjusted for certain observable price changes. This ASU also requires a qualitative impairment assessment of such equity investments and amends certain fair value disclosure requirements. The adoption of ASU No. 2016-01 did not have a material impact on the Company’s consolidated financial statements and resulted in enhancements to the financial instrument disclosures. On May 1, 2018, the Company early adopted ASU No. 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.” This ASU simplifies the application of the hedge accounting guidance and improves the financial reporting of hedging relationships to better portray the economic results of an entity’s risk management activities in its financial statements. The targeted improvements in ASU No. 2017-12 allowed the Company a one-time transfer of certain debt securities from HTM to AFS. The Company adopted this ASU using the modified retrospective approach. As part of this adoption, the Company made a one-time election to transfer eligible HTM securities to the AFS category in order to optimize the investment portfolio management for capital and risk management considerations. The Company transferred HTM securities with a carrying amount of $187.4 million, which resulted in an increase of approximately $400,000 to AOCI. Refer to Note 3 "Securities" and Note 9 "Stockholders' Equity" for further discussion regarding the adoption. On May 1, 2018, the Company early adopted ASU No. 2018-02, “Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” This ASU allows for a reclassification from AOCI to retained earnings for stranded tax effects resulting from the Tax Act and requires certain disclosures about the stranded tax effects. The Company reclassified approximately $107,000 from AOCI to retained earnings during the second quarter 2018. Refer to Note 9 "Stockholders' Equity" for further discussion regarding the adoption. The net impact to retained earnings of the adoption of ASU No. 2017-12 and ASU No. 2018-02 was $293,000. Recent Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842).” This ASU requires lessees to put most leases on their balance sheets, but recognize expenses in the income statement in a manner similar to today’s accounting. This ASU also eliminates the real estate-specific provisions and changes the guidance on sale-leaseback transactions, initial direct costs, and lease executory costs for all entities. For lessors, this ASU modifies the classification criteria and the accounting for sales-type and direct financing leases. This ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. The Company has implemented new lease systems in conjunction with the adoption. Management is progressing with implementation, including the review of service contracts for embedded leases, development of lease accounting policies, and evaluating potential new internal controls related to the implementation of this ASU. While the Company continues to evaluate this ASU and the effect of related disclosures, the primary effect of adoption will be to require recording right-of-use assets and corresponding lease obligations for current operating leases. Other implementation matters to be addressed include, but are not limited to, the determination of effects on the financial and capital ratios and the quantification of the impacts that this ASU will have on the Company's consolidated financial statements. Upon adoption, the Company expects to record a right of use asset and a corresponding lease liability for operating leases where the Company is the lessee. The potential impact to the Company’s consolidated financial statements is largely based on the present value of future minimum lease payments, the amount of which will depend upon the population of leases in effect at the date of adoption. Refer to Note 5 "Premises and Equipment” of the Company’s 2017 Form 10-K for information about the Company’s future minimum lease payment for leases that were present as of December 31, 2017. As previously disclosed, the Company’s 2017 Form 10-K does not include Xenith, which was acquired on January 1, 2018. The Company does not expect material changes to the recognition of operating lease expense in our consolidated statements of income. In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” This ASU updates the existing guidance to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. This ASU replaces the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The CECL model will replace the Company's current accounting for PCI and impaired loans. This ASU also amends the AFS debt securities OTTI model. This ASU is effective for fiscal years beginning after December 15, 2019. The Company has established a cross-functional governance structure for the implementation of CECL. The Company is continuing to evaluate the impact ASU No. 2016-13 will have on its consolidated financial statements. This ASU contains significant differences from existing GAAP, and the implementation of this ASU may result in increases to the Company's reserves for credit losses of financial instruments; however, the quantitative impact cannot be reasonably estimated since this ASU relies on economic conditions and trends that will impact the Company's portfolio at the time of adoption. In August 2018, the FASB issued ASU No. 2018-15, "Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract." This ASU amends the Intangibles—Goodwill and Other Topic of the Accounting Standards Codification to align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. This ASU will be effective for the Company for fiscal years beginning after December 15, 2019. Early adoption is permitted. The Company does not expect this ASU to have a material effect on its financial statements.