Share-Based Compensation and Benefit Plans (Summary of Shares Authorized and Available for Future Issuance Under Benefit and Compensation Plans) (Details) shares in Thousands	Dec. 31, 2018 shares
Profit sharing and savings plan [Member]
Share-Based Compensation and Benefit Plans
Shares authorized for issuance under compensation and benefit plans	4,200
Shares available for future issuance under compensation and benefit plans	349
Employee stock purchase plan [Member]
Share-Based Compensation and Benefit Plans
Shares authorized for issuance under compensation and benefit plans	4,250
Shares available for future issuance under compensation and benefit plans	594
Performance shares [Member] \| Restricted stock [Member]
Share-Based Compensation and Benefit Plans
Shares authorized for issuance under compensation and benefit plans	650
Shares available for future issuance under compensation and benefit plans	368
Stock option [Member] \| Employee stock option [Member]
Share-Based Compensation and Benefit Plans
Shares authorized for issuance under compensation and benefit plans	34,000
Shares available for future issuance under compensation and benefit plans	5,573
Stock option [Member] \| Director [Member]
Share-Based Compensation and Benefit Plans
Shares authorized for issuance under compensation and benefit plans	1,000
Shares available for future issuance under compensation and benefit plans	263

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.

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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