Boilerplate singleton / lazy initialiser
Based on the naming guidelines variables should be named using camelCase casing, at least if you don't have any internal naming guidelines.
So Lazy should become lazy or much better lazyManager to make it clear what's the lazy is about.



Otherwise your code looks good.
What I would like to suggest is to rename the class to better reflect its usage and makes it clear from the name what it is about. Maybe DatatableManager would be better.