Income Taxes - Net Operating Loss Carryforwards (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforward, deferred tax benefit	$ 35.6
State net operating loss carryforward, deferred tax benefit	23.8
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 169.5
Domestic Tax Authority [Member] | Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expire date	Dec. 31, 2032
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 410.3
State and Local Jurisdiction [Member] | Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expire date	Dec. 31, 2019
State and Local Jurisdiction [Member] | Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expire date	Dec. 31, 2038