Aggregate number of common shares reserved for future issuance.

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

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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ESPP plan details [Abstract]

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Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued, Percentage of Target

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Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized

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Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
ESPP plan details [Abstract]
Stock Issued During Period, Shares, Employee Stock Purchase Plans	126,046	61,691	126,046	61,691
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased	$ 15.60	$ 29.32	$ 15.60	$ 29.32
Restricted stock units and Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 46.6		$ 46.6
Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized			2 years 2 months 4 days
ESPP plan details [Abstract]
Granted			1,308,571
2012 Stock Option Plan \| Stock options and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Available for Grant	848,424		848,424
2012 Employee Stock Purchase Plan \| ESPP
ESPP plan details [Abstract]
Common Stock, Capital Shares Reserved for Future Issuance	1,063,572		1,063,572
2012 Equity Incentive Plan \| Restricted stock units and Performance stock units
ESPP plan details [Abstract]
Granted	145,877
Vesting period			3 years
Minimum \| 2012 Equity Incentive Plan \| Restricted stock units and Performance stock units
ESPP plan details [Abstract]
Shares issued, percentage of target			0.00%
Maximum \| 2012 Equity Incentive Plan \| Restricted stock units and Performance stock units
ESPP plan details [Abstract]
Shares issued, percentage of target			200.00%