Hi, Much depends on how these terms are used ina sentence, but here are some general comments. held in / detained 'Detained' sounds more offiical. eg a kidnapper would not usually be said to 'detain' someone document a eg a letter, a report / information eg the contents of a letter or report.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.