The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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-Topic 230
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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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- 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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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details) - $ / shares		12 Months Ended
Subsequent Events (Details) - $ / shares	Feb. 19, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
RSUs
Subsequent Event [Line Items]
Number of awards granted		197,078	227,481	137,034
Fair value on grant date		$ 42.56	$ 39.74	$ 42.20
Vesting period (in years)		3 years
RSUs \| Minimum
Subsequent Event [Line Items]
Vesting period (in years)		1 year
RSUs \| Maximum
Subsequent Event [Line Items]
Vesting period (in years)		5 years
Subsequent event
Subsequent Event [Line Items]
Dividends payable, per common share	$ 0.30
Subsequent event \| 2014 Long Term Incentive Plan \| RSUs
Subsequent Event [Line Items]
Number of awards granted	179,016
Fair value on grant date	$ 43.55
Subsequent event \| 2014 Long Term Incentive Plan \| RSUs \| Minimum
Subsequent Event [Line Items]
Vesting period (in years)	1 year
Subsequent event \| 2014 Long Term Incentive Plan \| RSUs \| Maximum
Subsequent Event [Line Items]
Vesting period (in years)	3 years