Borrowings Borrowings - Future Principal Payments on the Company’s Outstanding Debt (Details) $ in Millions	Dec. 31, 2018 USD ($)
Debt Disclosure [Abstract]
2019	$ 0.0
2020	0.0
2021	400.0
2022	300.0
2023	0.0
Thereafter	500.0
Total	$ 1,200.0

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Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Publisher FASB
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