Firefox ignoring min-height for height: 100% children

Firefox ignoring min-height for height: 100% children

This issue is causing me some headaches trying to put an iframe inside a page.  The page is automatically getting a min-height to account for fixed headers and footers and such, and that appears to be maintained on page transitions and window resizes.  The problem is that if I put <div style="height: 100%"><iframe style='height: 100%'></iframe></div> inside the page, FireFox doesn't render it right.  It seems to be ignoring the min-height as a height indicator altogether.  So, the iframe gets the default height of 150px and the div gets that plus padding, etc.  Is there any way to force FireFox to respect the min-height or otherwise force the div/iframe to be a correct 100% window height (minus header/footers)