The most common and most likely answer to this crossword clue is the 11 letter word CREDENTIALS
I've seen this crossword clue in The Times
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More clues leading to the result CREDENTIALS
Buddy explains!

The straight part
We know that "ID" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case id = credentials.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CREDENTIALS mean?
CREDENTIALS noun- (chiefly in the plural) documentary or electronic evidence that a person has certain status or privileges
- To furnish with credentials
- Documentary evidence of someone's right to credit or authority, especially such a document given to an ambassador by a country.