Stock-Based Compensation (Policies)	12 Months Ended
Dec. 31, 2018
Share-based Payment Arrangement [Abstract]
Share-based Compensation, Option and Incentive Plans	We recognize the fair value of stock-based compensation as expense over the requisite service period of the individual grantees, which generally equals the vesting period. We provide newly issued shares of our common stock and treasury stock to satisfy the issuance of PA, SVA, and RSU shares.

Disclosure of accounting policy for award under share-based payment arrangement. Includes, but is not limited to, methodology and assumption used in measuring cost.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b),(f)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

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