Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Allowances on accounts receivable, current	$ 9,398	$ 5,839
Accumulated depreciation on property and equipment	1,250,197
Accumulated depreciation on property and equipment		1,092,440
Accumulated amortization on other intangible assets	$ 437,886	$ 372,081
Treasury stock, common shares (in shares)	17,091,222	16,229,146
Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	600,000,000	600,000,000
Common stock, shares issued (in shares)	159,415,540	157,333,046
Common stock, shares outstanding (in shares)	142,324,318	141,103,900
Exchangeable Shares
Common stock, par value (in dollars per share)
Common stock, shares issued (in shares)	36,183	486,112
Common stock, shares outstanding (in shares)	36,183	486,112
Series G Preferred Stock
Preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Preferred stock, shares authorized (in shares)	0	1
Preferred stock, shares issued (in shares)	0	1
Preferred stock, shares outstanding (in shares)	0	1