Income Taxes - Summary of Operating Loss Carryforwards (Details) $ in Millions	Dec. 31, 2016 USD ($)
Operating Loss Carryforwards [Line Items]
U.S. federal and foreign NOLs	$ 65.3
State taxing jurisdiction NOLs	2.1
U.S. federal, foreign, and state tax credit carryforwards	0.1
U.S. federal capital loss carryforwards	5.2
Total	72.7
2017 Through 2026
Operating Loss Carryforwards [Line Items]
U.S. federal and foreign NOLs	0.0
State taxing jurisdiction NOLs	1.3
U.S. federal, foreign, and state tax credit carryforwards	0.0
U.S. federal capital loss carryforwards	5.2
Total	6.5
2027 Through 2036
Operating Loss Carryforwards [Line Items]
U.S. federal and foreign NOLs	65.3
State taxing jurisdiction NOLs	0.8
U.S. federal, foreign, and state tax credit carryforwards	0.1
U.S. federal capital loss carryforwards	0.0
Total	66.2
Indefinite
Operating Loss Carryforwards [Line Items]
U.S. federal and foreign NOLs	0.0
State taxing jurisdiction NOLs	0.0
U.S. federal, foreign, and state tax credit carryforwards	0.0
U.S. federal capital loss carryforwards	0.0
Total	$ 0.0