Loans - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2015 USD ($) contract	Dec. 31, 2014 USD ($) contract	Dec. 31, 2013 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract	1	7	14
Pre-modification outstanding recorded investment	$ 739	$ 1,650	$ 15,891
Recorded investment	689	1,073	9,423
Allowance for loan losses, troubled debt restructurings	37	21,000	3,700
Troubled debt restructuring, charge-offs	$ 50	$ 533	65
Troubled debt restructuring, payments received			$ 4,800
Commercial & Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract	1	4	8
Pre-modification outstanding recorded investment	$ 739	$ 915	$ 8,400
Recorded investment	$ 689	$ 353	$ 5,587
Commerical real estate [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract		1	1
Pre-modification outstanding recorded investment		$ 580	$ 2,562
Recorded investment		$ 570	$ 2,526
Construction, land & land development [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract		1	3
Pre-modification outstanding recorded investment		$ 30	$ 4,783
Recorded investment		$ 29	$ 1,164
Consumer and other [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| contract		1	2
Pre-modification outstanding recorded investment		$ 125	$ 146
Recorded investment		$ 121	$ 146

Represents the payments received on loans classified as troubled debt restructurings during the period.

No definition available.

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Balance Type:	debit
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- Definition

Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

+ Details

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