Income Taxes - Operating Loss Carryforwards (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
2019 - 2023 [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 1
State [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	23
State [Member] | 2024 - 2028 [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	16
State [Member] | 2029 [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 6