Subsequent Events	6 Months Ended
Jun. 30, 2018
Subsequent Events [Abstract]
Subsequent Events, Policy [Policy Text Block]	Subsequent Events No events occurred requiring disclosure other than the repurchase of an additional 0.2 million shares of our common stock for $4.2 million subsequent to June 30, 2018.

Disclosure of accounting policy for reporting subsequent events.

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

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