Significant Accounting Policies (Details 3) $ in Millions	Jan. 01, 2018 USD ($)
Nonredeemable preferred stock \| Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements
Cumulative effect adjustment due to ASU 2016-01	$ 0.1

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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