The UK government states that: “Intellectual property is something unique that you physically create. An idea alone is not intellectual property. For example, an idea for a book doesn’t count, but the words you’ve written do”. (https://www.gov.uk/intellectual-property-anoverview)."
This quote is taken from the 'Intellectual Property Note for Students' linked on the following BU webpage (scroll down page and under 'Policies and Procedures' heading, select the Intellectual Property link).