Space shuttle Endeavour and its seven astronauts safely returned to Earth on Sunday, taking a detour to sunny California after storms hit the main landing strip in Florida. Endeavour wrapped up a 16-day trip that left the international space station freshly remodeled and capable of housing bigger crews. The shuttle dropped off all kinds of home improvement equipment, including a new bathroom, kitchenette, exercise machine, two sleeping quarters and a recycling system designed to convert astronauts' urine and sweat into drinking water. But the mission wasn't without its problems. Astronaut Heidemarie Stefanyshyn-Piper let go of a $100,000 tool bag during the first spacewalk, muttering "Oh, great" as it floated away. And Endeavour's astronauts also had to put in extra effort to get the urine processor working. About seven liters (1.9 gallons) of recycled urine and condensation were coming back aboard Endeavour for extensive testing. No one at the space station will drink the recycled water until the equipment runs for 90 days and ground tests ensure it's safe. More samples will be returned on the next shuttle flight.