The MCA vide general circular no 37/2011, dated 7-6-2011 has mandated the following class of companies to file financial statements in XBRL format for FY 2010-11:
1) All companies listed in India and their Indian subsidiaries
2) All companies having a paid up capital of Rs.5 crore and above
3) All companies having a turnover of Rs.100 crore and above.
Thus if a private ltd company falls under category 2 or 3, i.e. if it has paid up capital of Rs 5 crore and above, or if has turnover of Rs 100 crore and above, the pvt ltd company should file its financial statment in XBRL format only.