Not really. Depending on the account value and the idle cash is it less.
Who cares about 10k lolz, where do you think I got that number, it's from the page you screenshotted.
I wouldn't there keep hundreds K of idle EUR cash in IB. Better to keep it a EUR bank account (where you pay no interest) and instant transfer to IB when you need. Or...
Get another currency exposure like USD.
Until USD rates become also negative ...
Can't use it for margin if it's in a bank account. Don't want USD exposure since I don't live in the US.