Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Receivable, allowance for credit loss	$ 32,472	$ 32,838
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, authorized (shares)	20,000,000	20,000,000
Preferred stock, issued (shares)	0	0
Preferred stock, outstanding (shares)	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, authorized (shares)	480,000,000	480,000,000
Common stock, issued (shares)	179,700,000	179,380,000
Common stock, outstanding (shares)	134,586,000	134,895,000
Treasury stock (shares)	45,114,000	44,485,000