Shareholders' Equity	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Shareholders' Equity	SHAREHOLDERS’ EQUITY Stock Repurchase Program On February 24, 2016, our Board of Directors authorized the repurchase of up to $150.0 million of our common stock in a stock repurchase program. The program replaced the prior $150.0 million program which was in effect at December 31, 2015 and had unused authorization of $11.9 million. During 2016, we repurchased 635,370 shares of our common stock in conjunction with our stock repurchase program at a total cost of $27.6 million based on settlement date. We had approximately $122.4 million of repurchase authority remaining under this program at December 31, 2016 based on settlement date. On April 25, 2017, the Board of Directors of the Company approved a new common stock repurchase program of up to $250.0 million. The program replaced the prior $150.0 million program that was authorized in February 2016 and had unused authorization of $114.6 million. The authorized amount included and was not in addition to any unspent amount remaining under the prior authorization in February 2016. Repurchases could be made at management’s discretion from time to time on the open market (either with or without a 10b5-1 plan) or through privately negotiated transactions. Share repurchases resulted in the shares being retired, and the cost of the shares acquired were treated as a reduction from common stock and retained earnings. The repurchase program had no time limit and could be suspended or discontinued at any time. On June 9, 2017, we entered into an agreement with a related party, The Duchossois Group ("TDG"), to repurchase 3,000,000 shares of the Company's common stock for $52.93 per share in a privately negotiated transaction. The aggregate purchase price was $158.8 million. For the year ended December 31, 2017, including the repurchase of 3,000,000 shares from TDG, we repurchased 3,231,087 shares of our common stock under the April 2017 stock repurchase program at a total cost of $171.7 million. We had approximately $78.3 million of repurchase authority remaining under this program at December 31, 2017. On November 29, 2017, the Board of Directors of the Company authorized a $500.0 million share repurchase program in a "modified Dutch auction" tender offer (the "Tender Offer") utilizing a portion of the proceeds from the Big Fish Transaction. The Company completed the Tender Offer on February 12, 2018, and repurchased 5,660,376 shares of the Company's common stock at a purchase price of $88.33 per share with an aggregate cost of $500.0 million, excluding fees and expenses related to the Tender Offer. On October 30, 2018, the Board of Directors of the Company approved a new common stock repurchase program of up to $300.0 million. The new program replaced the prior $250.0 million program that was authorized in April 2017 and had unused authorization of $78.3 million. The new authorized amount includes and is not in addition to any unspent amount remaining under the prior authorization. Repurchases may be made at management’s discretion from time to time on the open market (either with or without a 10b5-1 plan) or through privately negotiated transactions. The repurchase program has no time limit and may be suspended or discontinued at any time. For the year ended December 31, 2018, excluding the shares purchased under the Tender Offer, we repurchased 372,282 shares of our common stock under the October 2018 stock repurchase program at a total cost of $32.0 million. We had approximately $268.0 million of repurchase authority remaining under this program at December 31, 2018. Stock Split On October 30, 2018, the Company’s Board of Directors approved the Stock Split and an amendment to the Company’s Articles of Incorporation to increase the number of shares of common stock the Company is authorized to issue from 50,000,000 shares, no par value, to 150,000,000 shares, no par value. This amendment to the Company’s Articles of Incorporation became effective on January 25, 2019 and our common stock began trading at the split-adjusted price on January 28, 2019. All share and per-share amounts in the Company’s consolidated financial statements and related notes have been retroactively adjusted to reflect the effects of the Stock Split.

SHAREHOLDERS’ EQUITY

Stock Repurchase Program

On February 24, 2016, our Board of Directors authorized the repurchase of up to $150.0 million of our common stock in a stock repurchase program. The program replaced the prior $150.0 million program which was in effect at December 31, 2015 and had unused authorization of $11.9 million. During 2016, we repurchased 635,370 shares of our common stock in conjunction with our stock repurchase program at a total cost of $27.6 million based on settlement date. We had approximately $122.4 million of repurchase authority remaining under this program at December 31, 2016 based on settlement date.

On April 25, 2017, the Board of Directors of the Company approved a new common stock repurchase program of up to $250.0 million. The program replaced the prior $150.0 million program that was authorized in February 2016 and had unused authorization of $114.6 million. The authorized amount included and was not in addition to any unspent amount remaining under the prior authorization in February 2016. Repurchases could be made at management’s discretion from time to time on the open market (either with or without a 10b5-1 plan) or through privately negotiated transactions. Share repurchases resulted in the shares being retired, and the cost of the shares acquired were treated as a reduction from common stock and retained earnings. The repurchase program had no time limit and could be suspended or discontinued at any time.

On June 9, 2017, we entered into an agreement with a related party, The Duchossois Group ("TDG"), to repurchase 3,000,000 shares of the Company's common stock for $52.93 per share in a privately negotiated transaction. The aggregate purchase price was $158.8 million.

For the year ended December 31, 2017, including the repurchase of 3,000,000 shares from TDG, we repurchased 3,231,087 shares of our common stock under the April 2017 stock repurchase program at a total cost of $171.7 million. We had approximately $78.3 million of repurchase authority remaining under this program at December 31, 2017.

On November 29, 2017, the Board of Directors of the Company authorized a $500.0 million share repurchase program in a "modified Dutch auction" tender offer (the "Tender Offer") utilizing a portion of the proceeds from the Big Fish Transaction. The Company completed the Tender Offer on February 12, 2018, and repurchased 5,660,376 shares of the Company's common stock at a purchase price of $88.33 per share with an aggregate cost of $500.0 million, excluding fees and expenses related to the Tender Offer.

On October 30, 2018, the Board of Directors of the Company approved a new common stock repurchase program of up to $300.0 million. The new program replaced the prior $250.0 million program that was authorized in April 2017 and had unused authorization of $78.3 million. The new authorized amount includes and is not in addition to any unspent amount remaining under the prior authorization. Repurchases may be made at management’s discretion from time to time on the open market (either with or without a 10b5-1 plan) or through privately negotiated transactions. The repurchase program has no time limit and may be suspended or discontinued at any time.

For the year ended December 31, 2018, excluding the shares purchased under the Tender Offer, we repurchased 372,282 shares of our common stock under the October 2018 stock repurchase program at a total cost of $32.0 million. We had approximately $268.0 million of repurchase authority remaining under this program at December 31, 2018.

Stock Split

On October 30, 2018, the Company’s Board of Directors approved the Stock Split and an amendment to the Company’s Articles of Incorporation to increase the number of shares of common stock the Company is authorized to issue from 50,000,000 shares, no par value, to 150,000,000 shares, no par value. This amendment to the Company’s Articles of Incorporation became effective on January 25, 2019 and our common stock began trading at the split-adjusted price on January 28, 2019. All share and per-share amounts in the Company’s consolidated financial statements and related notes have been retroactively adjusted to reflect the effects of the Stock Split.