diff --git a/ui/jquery.ui.accordion.js b/ui/jquery.ui.accordion.js
index 9419089b5..c20097e70 100644
--- a/ui/jquery.ui.accordion.js
+++ b/ui/jquery.ui.accordion.js
@@ -550,11 +550,11 @@ $.extend( $.ui.accordion, {
 			// fix width before calculating height of hidden element
 			var s = options.toShow;
 			originalWidth = s[0].style.width;
-			s.width( parseInt( s.parent().width(), 10 )
-				- parseInt( s.css( "paddingLeft" ), 10 )
-				- parseInt( s.css( "paddingRight" ), 10 )
-				- ( parseInt( s.css( "borderLeftWidth" ), 10 ) || 0 )
-				- ( parseInt( s.css( "borderRightWidth" ), 10) || 0 ) );
+			s.width( s.parent().width()
+				- parseFloat( s.css( "paddingLeft" ) )
+				- parseFloat( s.css( "paddingRight" ) )
+				- ( parseFloat( s.css( "borderLeftWidth" ) ) || 0 )
+				- ( parseFloat( s.css( "borderRightWidth" ) ) || 0 ) );
 
 			$.each( fxAttrs, function( i, prop ) {
 				hideProps[ prop ] = "hide";