Condensed Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Unrealized gain (loss) on available-for-sale securities, tax (provision) benefit	$ 0.0	$ (0.3)	$ (0.8)	$ 0.9
Reclassification adjustment for realized net loss (gain) on available-for-sale securities included in net income, tax provisions	0.0	0.0	0.0	0.0
Unrealized (loss) gain on cash flow hedges, tax (provision) benefit	(0.2)		(1.3)
Unrealized (loss) gain on cash flow hedges, tax (provision) benefit		1.5		2.7
Reclassification adjustment for realized net loss (gain) on cash flow hedges included in net income, tax provisions (benefit)	$ 0.7		$ 1.5
Reclassification adjustment for realized net loss (gain) on cash flow hedges included in net income, tax provisions (benefit)		$ (0.5)		$ 0.3

Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580

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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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

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Amount of tax expense (benefit) 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).

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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