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ACQUISITIONS (Narrative) (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Feb. 01, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |  |
Cash paid in acquisition |  | $ 0 | $ 12,000 | $ 14,304,000
Merger-related costs |  | 0 | 27,824,000 | $ 39,728,000
Access National Bank |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Number of shares equivalent to each share of acquired entity | 0.75 |  |  |
Company's common shares issued | 15,842,026 |  |  |
Consideration transferred, fair value | $ 500,000,000.0 |  |  |
Cash paid in acquisition | $ 12,000 |  |  |
Merger-related costs |  | $ 0 | $ 26,200,000 |

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- Definition Business acquisition, number of shares equivalent to each share of acquired entity, + References No definition available. + Details
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- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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- Definition Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585 + Details
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