Note 11 - Borrowings and Financing Activities Senior Notes due 2027 (Details) - Senior Notes - Senior Notes Due 2027 - USD ($) $ in Millions	1 Months Ended
Jun. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument, Face Amount	$ 450.0
Proceeds from Issuance of Long-term Debt	$ 442.2
Debt Instrument, Interest Rate, Stated Percentage	4.875%	4.875%	4.875%
Debt Instrument, Redemption Price, Percentage	100.00%
Debt Instrument, Basis Spread on Variable Rate	0.50%
Percent of Stock With Ordinary Voting Rights That Company Must Retain In Order To Make Any Capital Stock Transactions	0.80

Percent of Stock With Ordinary Voting Rights That Company Must Retain In Order To Make Any Capital Stock Transactions

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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