Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Other comprehensive income/(loss), tax	$ 2.3	$ 4.8
Reclassifications to earnings on available-for-sale securities	0.0	0.0
Reclassifications to earnings of gains/(losses) on cash flow hedging instruments	0.5	$ (0.9)
ASU 2018-02 [Member]
Reclassification to retained earnings related to cash flow hedges and investment portfolio credit risk	$ 3.0

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

No definition available.

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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (d)
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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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