Convert Nvarchar Values To Integer

I have imported a text file with various data into sql table. all these values have been imported as nvarchar. I need to convert these into Integer. the format of the values is 10length i.e. 0000000.00.
example of data:
0001028.99 - needs to be shown as 1028.99
222.00 - needs to be shown as 222.00
0000190.89 - needs to be shown as 190.89
2708.99 - needs to be shown as 2708.99
00000-50.99 - needs to be shown as -50.99
-109.79 - needs to be shown as -109.70

as you can see some of the values have leading zeros and some don't.
i have tried converting from nvarchar to int and i get the error cannot convert nvarchar to int, i believe it may be because the data contains negative values as well as positive values.

Is there a split function or position function which i can use to extract the data? or any other methods which i can use would be really helpful.

Thanks