Stock Compensation Plans Narratives (Details) - West Bancorporation, Inc. 2012 Equity Incentive Plan [Member] - Common stock [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock compensation plan [Line Items]
Stock compensation plan, restricted stock, number of shares authorized	800,000
Stock compensation plan, restricted stock, number of shares available for grant	437,022	564,857
Restricted stock units (RSUs) [Member]
Stock compensation plan [Line Items]
Projected forfeitures on restricted stock awards	0
Stock compensation plan, restricted stock, forfeited in period, shares	0
Stock compensation plan, restricted stock, vested in period, fair value	$ 1,118	$ 818
Stock compensation plan, restricted stock, nonvested awards, total compensation cost not yet recognized, period for recognition	3 years 1 month 6 days
Restricted stock or unit expense	$ 0
Shares of common stock per restricted stock unit	1
Stock compensation expense	$ 1,166	$ 633	$ 378
Employee stock compensation, nonvested awards, total compensation cost not yet recognized, restricted stock	$ 3,000

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares related to Restricted Stock Award forfeited during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher SEC
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The number of shares projected to be forfeited under restricted stock awards.

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The number of shares of common stock each restricted stock unit entitles a participant to receive on the vesting date.

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