Premises and Equipment - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Premises and equipments
Premises and equipment, gross	$ 331,250	$ 322,872
Less accumulated depreciation	(125,110)	(114,020)
Premises and equipment, net	206,140	208,852
Land and land improvements
Premises and equipments
Premises and equipment, gross	78,066	80,335
Buildings and improvements
Premises and equipments
Premises and equipment, gross	153,980	148,048
Furniture and equipment
Premises and equipments
Premises and equipment, gross	93,854	82,775
Construction in progress
Premises and equipments
Premises and equipment, gross	$ 5,350	$ 11,714

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depreciation, depletion and amortization of physical assets 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, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02(13))
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