Condensed Statements of Cash Flows - Parent Company Only (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Flows from Operating Activities:
Net income	$ 5,941	$ 5,426	$ 5,272	$ 5,103	$ 5,838	$ 5,063	$ 4,739	$ 4,400	$ 21,742	$ 20,040	$ 16,891
Adjustments to reconcile net income to net cash provided by operating activities:
Realized investment securities (gains) losses, net									(47)	(223)	0
Depreciation									921	853	786
Gain on disposition of premises									6	(1,069)	9
Write-down of other real estate owned									0	1,786	1,341
Deferred income taxes (benefits)									82	535	1,147
Change in assets and liabilities:
(Increase) decrease in other assets									2,937	(450)	580
Increase (decrease) in accrued expenses and other liabilities									(196)	(476)	(1,728)
Cash Flows from Investing Activities:
Proceeds from paydown on securities available for sale									49,665	56,450	74,202
Purchases of premises									(2,502)	(5,298)	(2,199)
Proceeds from sales of other real estate owned									2,227	2,103	1,744
Proceeds from settlement of other assets									3,593	0	0
Cash Flows from Financing Activities:
Proceeds from long-term debt									0	0	16,000
Principal payments on long-term debt									(4,261)	(3,260)	(830)
Common stock cash dividends									(9,952)	(7,842)	(6,995)
Repurchase and cancellation of common stock									0	0	(15,774)
Cash:
Purchases of premises financed by issuance of long-term debt									0	0	765
Transfer of investment securities to other assets, sale not settled									0	3,593	0
Parent Company [Member]
Cash Flows from Operating Activities:
Net income									21,742	20,040	16,891
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in net income of West Bank									(22,546)	(19,773)	(18,609)
Equity in net income of West Bancorporation Capital Trust I									(21)	(21)	(21)
Dividends received from West Bank									13,900	12,700	19,200
Dividends received from West Bancorporation Capital Trust I									21	21	21
Realized investment securities (gains) losses, net									0	493	0
Amortization									23	26	20
Depreciation									139	39	43
Gain on disposition of premises									0	(1,627)	0
Write-down of other real estate owned									0	1,681	1,341
Loss on sale of other real estate owned									8	10	70
Deferred income taxes (benefits)									99	362	(412)
Change in assets and liabilities:
(Increase) decrease in other assets									1,428	(1,248)	(217)
Increase (decrease) in accrued expenses and other liabilities									(31)	(32)	(137)
Net cash provided by operating activities									14,762	12,671	18,190
Cash Flows from Investing Activities:
Proceeds from paydown on securities available for sale									0	85	0
Proceeds from sale of premises									0	3,000	0
Purchases of premises									(1,386)	(4,097)	(1,165)
Proceeds from sales of other real estate owned									2,227	1,530	280
Proceeds from settlement of other assets									3,593
Capital contribution to West Bank									0	0	(10,000)
Net cash provided by (used in) investing activities									4,434	518	(10,885)
Cash Flows from Financing Activities:
Proceeds from long-term debt									0	0	16,000
Principal payments on long-term debt									(4,261)	(3,260)	(830)
Common stock cash dividends									(9,952)	(7,842)	(6,995)
Repurchase and cancellation of common stock									0	0	(15,774)
Net cash provided by (used in) financing activities									(14,213)	(11,102)	(7,599)
Net increase (decrease) in cash									4,983	2,087	(294)
Cash:
Beginning				$ 8,792				$ 6,705	8,792	6,705	6,999
Ending	$ 13,775				$ 8,792				13,775	8,792	6,705
Purchases of premises financed by issuance of long-term debt									0	0	765
Transfer of investment securities to other assets, sale not settled									$ 0	$ 3,593	$ 0