Originally it had a name that was easy to understand. It was called Total Credit Market Debt, and it included all government and private debt. Then when people started to make it a popular metric the Fed changed the name and made it incomprehensible - All Sectors; Credit Market Instruments; Liability, Level.
The name change didn't diminish its popularity so they opted for the final solution. FRED has discontinued publishing the data. It's still included in the Fed's quarterly Z.1 release under L.100 Domestic Nonfinancial Sectors so if you know Excel you can continue to chart it.
http://www.chartword.com/search/label/TCMD
Meet the new Total Credit Market Debt equivalent: All Sectors; Total Debt Securities; Liability...
