dovecot Connection closed IDLE running

[Adrian Minta]

Hello,

sometimes I get lines like this on mail log.

Mar 11 07:57:14 mail2 dovecot: imap(john.one at domain.ro): Connection 
closed (IDLE running for 0.006 + waiting input for 1765.640 secs, 0.001 
in locks, 2 B in + 10+0 B out, state=wait-input) in=323201 out=3177999

Mar 11 07:58:56 mail3 dovecot: imap(john.two at domain.ro): Connection 
closed (IDLE running for 0.005 + waiting input for 3535.348 secs, 0.001 
in locks, 2 B in + 10+0 B out, state=wait-input) in=1627 out=14872
Mar 11 08:38:50 mail2 dovecot: imap(sam at domain.ro): Connection closed 
(IDLE running for 2.225 + waiting input for 267.413 secs, 0.005 in 
locks, 2 B in + 10+0 B out, state=wait-input) in=7212 out=2503
Mar 11 09:01:23 mail2 dovecot: imap(john.one at domain.ro): Connection 
closed (FETCH running for 8.784 + waiting input for 0.001 secs, 0.008 in 
locks, 24 B in + 6291+6291 B out, state=wait-input) in=196 out=43968
Mar 11 09:02:57 mail1 dovecot: imap(bush at domain.ro): Connection closed 
(IDLE running for 0.006 + waiting input for 1031.530 secs, 0.001 in 
locks, 2 B in + 10+0 B out, state=wait-input) in=9157 out=381003
Mar 11 09:33:31 mail2 dovecot: imap(john.one at domain.ro): Connection 
closed (IDLE running for 0.008 + waiting input for 1737.458 secs, 0.001 
in locks, 2 B in + 41+0 B out, state=wait-input) in=7871 out=322122

Our dovecot version is 2.2.27 and the mail storage is maildir.

What is the cause ? Could this negatively affects the users ?

-- 
Best regards,
Adrian Minta