Newly Adopted Accounting Standards and Accounting Standards Not Yet Implemented - Adjustments Due to ASU 2016-02 (Details) - Accounting Standards Update 2016-02 $ in Millions	Jan. 01, 2019 USD ($)
Operating lease right-of-use assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	$ 109.3
Total assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	109.3
Accounts payable and accrued expenses
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	41.8
Total current liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	41.8
Operating lease liabilities, less current portion
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	67.5
Total liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement	$ 109.3