def find_language(regnskab_dict):
    """ Detects language from dict of text fields """
    for key, regnskab_tuples in regnskab_dict.items():
        for t in regnskab_tuples:
            if t.unitIdXbrl is not None and t.unitIdXbrl[0:5] == 'lang:':
                return t.unitIdXbrl[5:]
    return 'da'