As of December 31, | |||||||||||||||
Pension Benefits | Other Postretirement Benefits | ||||||||||||||
2013 | 2012 | 2013 | 2012 | ||||||||||||
(In millions) | |||||||||||||||
Funded status — STPNOC benefit plans | $ | (42 | ) | $ | (76 | ) | $ | (52 | ) | $ | (56 | ) | |||
Net periodic benefit costs | 11 | 10 | 8 | 8 | |||||||||||
Other changes in plan assets and benefit obligations recognized in other comprehensive income | (31 | ) | 14 | (10 | ) | 1 |