Stock Repurchase Plan (Notes)	12 Months Ended
	Dec. 31, 2021
Stock Repurchase Plan [Abstract]
Stock repurchase plan [Text Block]	Stock Repurchase Plan In early December 2021, our Board of Directors authorized a new stock repurchase program for up to $500.0 million (the “December 2021 Program”), which superseded our previous stock repurchase program. Under the December 2021 program, we may purchase shares of our common stock from time to time in the open market or privately negotiated transactions. We are not obligated to acquire any shares under the program, and the program may be suspended or discontinued at any time. Under the December 2021 Program, 2,829,700 shares of our common stock were repurchased for an aggregate purchase price of approximately $140.0 million and $360.0 million remains available for repurchases. Under previous repurchase programs, 5,069,108 shares of our common stock were repurchased for an aggregate purchase price of $250.0 million during 2021. During 2020, 1,463,377 shares of our common stock were repurchased for an aggregate purchase prices of $26.6 million.