A valving device includes a tubular with a port and a sleeve slidably sealingly engaged with the tubular between a first position and a second position. The sleeve is configured to occlude the port when in the first position and uncover the port when in the second position. The valving device is configured such that pressure inside the tubular does not urge the sleeve toward the second position while pressure applied radially outwardly of the tubular and the sleeve urge the sleeve toward the second position.