Goodwill and Other Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Amortizable intangible assets:
Amortization expense	$ 268us-gaap_AmortizationOfIntangibleAssets	$ 331us-gaap_AmortizationOfIntangibleAssets
Estimated amortization expense
For the year ending December 31, 2015	1,074
For the year ending December 31, 2016	835
For the year ending December 31, 2017	597
For the year ending December 31, 2018	429
For the year ending December 31, 2019	260
For the year ending December 31, 2020	92
Core Deposits
Amortizable intangible assets:
Intangible asset - gross	30,578		30,578
Less: accumulated amortization	(30,578)		(30,578)
Customer and Contract
Amortizable intangible assets:
Intangible asset - gross	8,234		6,197
Acquisitions	262		2,037
Less: accumulated amortization	(5,469)		(5,201)
Intangible asset - net	$ 3,027		$ 3,033

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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