On the passport validity rule as applied by airlines from a recently closed thread :

I can only speak 100% for the airline that I work for, but we would not blankly apply the "6 months validity" thing. All countries have different rules and i believe that all airlines would (should) apply the rules according to your destination.

It is right to say that Thailand (currently) requires validity "for the period of intended stay" (those holding a form of residency are exempt from this as they can renew their passport from their embassy).

Regarding re-entry to Indonesia that shouldn't be an issue IF you are residents with PROOF of residency.

Of course, renewing your passports is always a good move when getting close to that "6 month window" as you might fall foul of it elsewhere.

Please note that some countries don't just require "6 months validity on arrival" or 3 months etc) ... some require "beyond the period of intended stay", which means that your passport validity is calculated not from your arrival date, but from your departure date (thus, if you arrive for a 2 week holiday, your passport must be valid 6 months and 2 weeks). Does not apply to residents.

I've veered off the Thailand-specific, sorry. But hopefully it's of use to someone.