Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Polsinelli
Related Party Transaction [Line Items]
Legal services obtained	$ 1.8	$ 1.1	$ 3.3	$ 1.7
Accounts payable for legal services	1.2	1.1	1.2	1.1
Family Member of the Company's Executive Vice President \| Legal Services from Segal McCambridge Singer & Mahone
Related Party Transaction [Line Items]
Legal services obtained	$ 0.0	$ 0.2	$ 0.1	$ 0.4

Amount for accounts payable to related parties.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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