[BroJoeK]

henkster: "Yeah, they all knew.
But it was too horrible to admit it to themselves."

I'd put it this way:
Some knew little or nothing.
Many more knew "something".
Very, very few knew everything.

[henkster]

I think they knew the Jews and other “undesirables” were being murdered. But as you say, only a very few knew all of the details.

[colorado tanker]

It still sickens me to read such matter of fact accounts by Germans of what they were doing or proposing.

Goebbels was one of those who knew everything. A few weeks ago he said they would go down as the greatest heroes or greatest criminals in history. He really should have known how that would turn out.