Background not showing in new div without adding height.

I have problem adding an inner background for my blog. The inner background is established in a new div (#inner-background) that cover up the entire webpage except the tag.

I use the body tag for my main background and the #inner-background tag for the inner background with 1000px for the width. However, the inner background does not show up. I have tried clear: both, display: block but it still didn't work.

This is the following css:
#inner-background { clear: both; margin: 0 auto; display: block; width: 1000px; background: #efefee; }

Moment later, I try to add a fixed height to the css code and the background eventually showing up depending on the value of the height.
I have also tried height: 100% but the background won't show up.

This is the following css:
#inner-background { clear: both; margin: 0 auto; display: block; width: 1000px; height: 1000px; background: #efefee; }

Please help me to identify the problem, I want the inner background to cover up the entire page with 1000px width but so far I was unable to achieve that.