Condensed Statements of Income- 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
Operating Income
Gain (loss) on disposition of premises									$ (6)	$ 1,069	$ (9)
Realized investment securities gains (losses), net									47	223	0
Operating Expenses [Abstract]
Interest on subordinated notes									705	754	711
Interest on long-term debt									232	297	188
Occupancy									4,105	4,165	3,906
Other real estate owned expense									10	1,865	1,359
Income before income taxes	$ 8,537	$ 7,892	$ 7,633	$ 7,377	$ 5,985	$ 7,425	$ 6,920	$ 6,359	31,439	26,689	24,211
Income tax benefits	2,596	2,466	2,361	2,274	147	2,362	2,181	1,959	9,697	6,649	7,320
Net income	$ 5,941	$ 5,426	$ 5,272	$ 5,103	$ 5,838	$ 5,063	$ 4,739	$ 4,400	21,742	20,040	16,891
Parent Company [Member]
Operating Income
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
Gain (loss) on disposition of premises									0	1,627	0
Realized investment securities gains (losses), net									0	(493)	0
Intercompany rental income									207	126	145
Other rental income									43	0	0
Total operating income									22,817	21,054	18,775
Operating Expenses [Abstract]
Interest on subordinated notes									705	753	711
Interest on long-term debt									232	297	188
Occupancy									170	78	49
Other real estate owned expense									10	1,725	1,511
Other expenses									486	604	686
Total operating expenses									1,603	3,457	3,145
Income before income taxes									21,214	17,597	15,630
Income tax benefits									(528)	(2,443)	(1,261)
Net income									$ 21,742	$ 20,040	$ 16,891