It's a perfect example for using Nested Styles. You'll create character styles for each of the kinds of formatting, then define how they are called out (probably a tab character) in the Nested Styles section of a paragraph style.
Look in InDesign Help for Nested Styles.
Looks to me like you only need one character style. Make the paragraph style using the bold font, then for nested styles: None through 1 tab, then a character style to change the weight through 1 word.
Daniel's screen cap is essentially what I said, but slightly different triggering. Mine left the tabs bold, his makes them lighter. Either is fine in this situation since a tab really has no weight. I picked the "one word" though because I wasn't sure what the separaor was between the two numbers, and that way I didn't need to worry about it.