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 of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Premises and Equipment, Net (Details) (USD $)	12 Months Ended
Premises and Equipment, Net (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Premises and equipment before accumulated depreciation	$ 181,235,000us-gaap_PropertyPlantAndEquipmentGross	$ 175,827,000us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation	91,977,000	87,500,000
Total premises and equipment	89,258,000us-gaap_PropertyPlantAndEquipmentNet	88,327,000us-gaap_PropertyPlantAndEquipmentNet
Rental expense	8,000,000us-gaap_OperatingLeasesRentExpenseNet	7,500,000us-gaap_OperatingLeasesRentExpenseNet	6,400,000us-gaap_OperatingLeasesRentExpenseNet
Future Minimum Rental Payments [Abstract]
2015	7,369,000
2016	7,215,000
2017	6,811,000
2018	6,122,000
2019	5,655,000
Thereafter	26,257,000
Total	59,429,000
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment before accumulated depreciation	122,400,000	120,098,000
Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment before accumulated depreciation	$ 58,835,000	$ 55,729,000
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Building and Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	15 years
Building and Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	40 years