The most common and most likely answer to this crossword clue is the 5 letter word POLER
P
O
L
E
R
More clues leading to the result POLER
Buddy explains!

The straight part
We know that "Idle Aussie" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case idle aussie = poler.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 POLER mean?
POLER noun- One who propels a boat using a pole.
- A horse harnessed alongside the shaft or pole of a vehicle.
- An extortioner.