During login, Google Chrome OS can authenticate against a server (online) or using a cached password (offline).
When this policy is set to a value of -1, the user can authenticate offline indefinitely. When this policy is set to any other value, it specifies the length of time since the last online authentication after which the user must use online authentication again.
Leaving this policy not set will make Google Chrome OS use a default time limit of 14 days after which the user must use online authentication again.
This policy affects only users who authenticated using SAML.
The policy value should be specified in seconds.