Share-Based Compensation and Employee Ownership Plans Restricted Shares and Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Mar. 31, 2016	Mar. 31, 2020	Mar. 31, 2019
Equity Plans \| Restricted Shares and Restricted Stock Units (RSUs)
Nonvested Restricted Shares and Restricted Stock Units
Balance outstanding, beginning of period, shares		5,364,486	5,962,295
Granted, shares		2,140,932	1,781,949
Vested, shares		(640,084)	(768,468)
Canceled, shares		(87,348)	(233,333)
Forfeited, shares		(30,562)	(144,346)
Balance outstanding, end of period, shares		6,747,424	6,598,097
Weighted-Average Grant Date Fair Value
Balance outstanding, beginning of period, in dollars per share		$ 16.67	$ 15.73
Granted, in dollars per share		17.39	16.97
Vested, in dollars per share		14.63	16.69
Canceled, in dollars per share		14.80	14.12
Forfeited, in dollars per share		15.86	13.84
Balance outstanding, end of period, in dollars per share		$ 17.12	$ 16.05
Unrecognized compensation expense		$ 86.1
Weighted-average recognition period for unrecognized compensation expense		2 years 8 months 23 days
Equity Plans \| Performance based restricted stock
Nonvested Restricted Shares and Restricted Stock Units
Granted, shares	1,033,333
Vested, shares		(145,986)
Forfeited, shares		(320,681)
Non-employee Director \| Equity Plans \| Restricted Stock Units (RSUs)
Nonvested Restricted Shares and Restricted Stock Units
Balance outstanding, beginning of period, shares		216,912
Balance outstanding, end of period, shares		216,912
Weighted-Average Grant Date Fair Value
Granted, shares		0
Maximum
Nonvested Restricted Shares and Restricted Stock Units
Percent of RSU's earned		200.00%
Minimum
Nonvested Restricted Shares and Restricted Stock Units
Percent of RSU's earned		0.00%

Percent of RSU's earned

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Canceled in Period

+ References

No definition available.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Canceled in Period, Weighted Average Grant Date Fair Value

+ References

No definition available.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Net number of non-option equity instruments granted to participants.

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