PREMISES AND EQUIPMENT, NET - Summary of Premises, Equipment, and Capital Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 182,666	$ 174,398
Less accumulated depreciation	(54,645)	(45,004)
Premises and equipment, net	128,021	129,394
Land
Property, Plant and Equipment [Line Items]
Premises and equipment	9,020	9,020
Building and Improvement
Property, Plant and Equipment [Line Items]
Premises and equipment	109,450	109,228
Furniture, fixture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment	48,923	41,576
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Premises and equipment	15,052	13,531
Construction in process
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 221	$ 1,043

Cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land or leased assets).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Gross amount of long-lived physical assets excluding assets held under lease agreements used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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