Organization and Basis of Presentation - Narrative (Details) - SWNB Bancorp, Inc. (“SWNB”) - Expected to close $ in Millions	3 Months Ended
Sep. 30, 2018 USD ($) branch
Business Acquisition [Line Items]
Total assets of entity to be acquired	$ 411.0
Number of retail branches \| branch	6
Estimate of aggregate consideration upon acquisition	$ 76.7

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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