I have a DF that lists IDs by date like this:

```
Date          Ben     James
12/10/17      1294    NA     
12/11/17      NA      4523      
12/12/17      8959    3246      
12/13/17      2345    NA        
12/14/17      NA      NA        
12/15/17      0303    8877      
12/16/17      NA      1427 

```

The number of "name" columns is variable, so on another day I might have a DF that looks like this:

```
Date          Ben     James     Alex
12/10/17      1294    NA        3754
12/11/17      NA      4523      1122
12/12/17      8959    3246      5582
12/13/17      2345    NA        NA
12/14/17      NA      NA        0094
12/15/17      0303    8877      NA
12/16/17      NA      1427      NA

```

I want to put the 3 most recent IDs for each name column into a new dataframe, like this:

```
IDs
8959
2345
0303
3246
8877
1427
1122
5582
0094

```

I just need the IDs in the new DF. I don't care about labeling them by name or date.