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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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Premises and Equipment - Components and Depreciation and Amortization Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2016
Components of premises and equipment
Premises and equipment	$ 490,231	$ 479,936
Less: Accumulated depreciation and amortization	185,127	172,476
Net book value	305,104	307,460	$ 302,059
Depreciation and amortization expenses	14,546	13,124
Occupancy
Components of premises and equipment
Depreciation and amortization expenses	9,039	8,540
Equipment
Components of premises and equipment
Depreciation and amortization expenses	5,507	4,584
Buildings
Components of premises and equipment
Premises and equipment	277,133	273,700
Furniture and equipment
Components of premises and equipment
Premises and equipment	74,965	61,318
Land
Components of premises and equipment
Premises and equipment	89,164	88,696
Leasehold improvements
Components of premises and equipment
Premises and equipment	$ 48,969	$ 56,222