Conveyance of Future Hard Minerals Royalty Revenues (Tables)

3 Months Ended

Mar. 31, 2016

Deferred Revenue Disclosure [Abstract]

Other Commitments [Table Text Block]

The following summarizes the future amounts, prior to the 3% to 4% of any excess described above, that the third party expects to receive:

millions
2016	$	25
2017	50
2018	50
2019	52
2020	56
Later years	320
Total	$	553