Commitments and Contingencies - Commitments and obligations (Details) $ in Millions	Dec. 31, 2016 USD ($)
Total	$ 476
Less than one year	441
One to three years	34
Three to five years	1
Purchase Obligation
Total	277
Less than one year	247
One to three years	29
Three to five years	1
Guarantees
Total	150
Less than one year	150
Letters Of Credit [Member]
Total	49
Less than one year	44
One to three years	$ 5