| Component: (Network and Table) | |
|---|---|
| Network | 06131 - Disclosure - Income taxes (Details 1) (http://advisoryboardcompany.com/role/IncomeTaxesDetails1) |
| Table | (Implied) |
| Reporting Entity [Axis] | 0001157377 (http://www.sec.gov/CIK) |
| Income Taxes [Abstract] | Period [Axis] | ||
|---|---|---|---|
2011-04-01 - 2012-03-31 | 2010-04-01 - 2011-03-31 | 2009-04-01 - 2010-03-31 | |
Income Taxes [Abstract] | |||
Statutory rates to income before provision for income taxes | |||
Statutory U.S. federal income tax rate | .350 | .350 | .350 |
State income tax, net of U.S. federal income tax benefit | .055 | .055 | .057 |
Tax-exempt interest income | (.015) | (.015) | (.027) |
Washington, D.C. QHTC income tax credits | (.031) | (.073) | (.091) |
Other permanent differences, net | .027 | .032 | .054 |
Effective tax rate on continuing operations | .386 | .349 | .343 |