Net Income (Loss) Per Share (Basic and Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Earnings Per Share [Abstract]
Net income (loss) attributable to Concur	$ (8,206)	$ 6,906	$ (4,838)	$ (868)	$ (14,031)	$ 2,266	$ (2,629)	$ 3,651	$ 3,359	$ 3,634	$ 6,718	$ 6,433	$ (7,006)	$ (10,743)	$ 20,144
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Basic													54,595	53,464	50,141
Dilutive effect of share-based equity awards													0	0	2,949
Diluted													54,595	53,464	53,090
Earnings Per Share, Basic and Diluted [Abstract]
Basic, in Dollars Per Share	$ (0.15)	$ 0.13	$ (0.09)	$ (0.02)	$ (0.26)	$ 0.04	$ (0.05)	$ 0.07	$ 0.06	$ 0.07	$ 0.14	$ 0.13	$ (0.13)	$ (0.20)	$ 0.40
Diluted, in Dollars Per Share	$ (0.15)	$ 0.12	$ (0.09)	$ (0.02)	$ (0.26)	$ 0.04	$ (0.05)	$ 0.07	$ 0.06	$ 0.07	$ 0.13	$ 0.12	$ (0.13)	$ (0.20)	$ 0.38