The Window Menu

Window → Close (Ctrl+W)

Close the active window.

Window → Close All

Close all opened windows.

Window → MDI Mode → Childframe Mode

Switch to Childframe user interface mode.

Window → MDI Mode → IDEAl Mode

Switch to IDEAl user interface mode.

Window → Next Window (Alt+Right)

Switch to the next window.

Window → Previous Window (Alt+Left)

Switch to the previous window.

The last items in this menu show the currently opened window names.