Stockholders' Equity Stockholders' Equity	3 Months Ended
Mar. 31, 2019
Equity [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	4. Stockholders' Equity Share Repurchases During the first quarter of 2019, the Company repurchased 505,448 shares of the Company's common stock in the open market at an average price of $59.35 per share, for a total of $30.0 million. As of March 31, 2019, approximately $70.0 million remains available for repurchase under the previously announced $100.0 million share repurchase authorization (which expires at the end of 2019).

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

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