The components of income tax expense were as follows (in millions): 
 
2016
 
2015
 
2014
Current income tax expense:
 
 
 
 
 
Federal
$
392

 
$
397

 
$
229

State
48

 
30

 
27

Total current income tax expense
440

 
427

 
256

 
 
 
 
 
 
Deferred income tax expense:
 

 
 

 
 

Federal
77

 
60

 
103

State
14

 
(23
)
 
11

Total deferred income tax expense
91

 
37

 
114

Income tax expense
$
531

 
$
464

 
$
370