Biden's Involvement in the Detroit Bankruptcy?

In the Democratic Primary debate last night, former Vice-President Joe Biden claimed to have been deeply involved in the Detroit bankruptcy: 

Q (Tapper): What do you say to progressives who worry that your proposals are not ambitious enough to energize the progressive wing of your party, which you will need to beat Donald Trump?

A (Biden): ... Number three, number three, I also was asked, as the mayor of Detroit can tell you, by the president of the United States to help Detroit get out of bankruptcy and get back on its feet. I spent better part of two years out here working to make sure that it did exactly that.

What on earth is Joe Biden talking about? I followed the Detroit bankruptcy case fairly closely and never once heard of any involvement from Biden. A google search for "Biden Detroit bankruptcy" shows an involvement consisting of all of one lunch with the Mayor of Detroit.  Maybe Biden was deeply involved behind the scenes, but I doubt it, as the federal government simply didn’t do anything to help out Detroit. Perhaps he was referring to the GM/Chrysler bankruptcies? If so, there was important federal involvement as a lender, but Joe Biden was not an important player in those cases either as far as I know.

If others know more, it would be interesting to hear, but as far as I can tell, Biden is claiming credit for things that he had no involvement in.