Need to find gap between start and end dates more than 20 days for multiple data ranges with overlaps. One Id has multiple start dates and end dates. Following Id 1 has two gaps less that 20 day. It should be considered as one range from 10/01/2012 to 10/30/2014 without any gap.

1   10/01/2012  02/01/2013
1   01/01/2013  01/31/2013
1   02/10/2013  03/31/2013
1   04/15/2013  10/30/2014

Id 2 has a gap more than 20 days between end date 01/30/2013 and start date 05/01/2013. It has to be captured.

2   01/01/2013  01/30/2013
2   05/01/2013  06/30/2014
2   07/01/2013  02/01/2014

Id 3 should be considered as one range from 01/01/2012 to 06/01/2014 without any gap. The gap between end date 02/28/2013 and start date 07/01/2013 should be ignored because range from 01/01/2012 to 01/01/2014 cavers a gap.

3   01/01/2012  01/01/2014
3   01/01/2013  02/28/2013
3   07/01/2013  06/01/2014

The cursor can do it but it works extremely slow and not acceptable.

SQL fiddle http://sqlfiddle.com/#!3/27e3f/2/0