Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Activities:
Net income (loss)	$ (573.4)	$ (929.5)	$ 140.2
Adjustments to reconcile net income (loss) to net cash generated by operating activities:
Depreciation and amortization	823.3	770.9	357.5
Equity-based compensation	115.0	90.8	44.9
Deferred income taxes	(154.7)	(260.8)	(49.2)
Asset impairments	206.7	376.1	15.0
Changes in assets and liabilities:
Accounts receivable	228.4	258.8	65.1
Inventories	(100.5)	489.1	(48.5)
Prepaid expenses and other current assets	(17.2)	19.5	1.0
Accounts payable and other accrued liabilities	(175.2)	(274.0)	(0.8)
Other noncurrent liabilities	(4.0)	7.2	(54.6)
Other noncurrent assets	28.8	46.0	(8.0)
Other	59.0	2.3	31.5
Net cash generated by operating activities	436.2	596.4	494.1
Investing Activities:
Additions to property, plant and equipment	(121.2)	(104.1)	(82.3)
Proceeds from sale of property, plant and equipment	5.0	1.6	12.9
Proceeds from sale of long-term investments		9.3
Cash paid for ARRIS acquisition, net of cash acquired		(5,053.4)
Cash paid for Cable Exchange acquisition	(3.5)	(11.0)
Other	(0.5)	2.7	5.1
Net cash used in investing activities	(120.2)	(5,154.9)	(64.3)
Financing Activities:
Long-term debt repaid	(1,282.0)	(3,061.3)	(550.0)
Long-term debt proceeds	950.0	6,933.0	150.0
Debt issuance costs	(11.7)	(120.8)
Debt extinguishment costs	(17.9)
Series A convertible preferred stock proceeds		1,000.0
Dividends paid on Series A convertible preferred stock	(14.3)	(40.7)
Deemed dividend paid on Series A convertible preferred stock		(3.0)
Proceeds from the issuance of common shares under equity-based compensation plans	9.0	4.6	6.1
Tax withholding payments for vested equity-based compensation awards	(16.9)	(13.2)	(15.7)
Net cash generated by (used in) financing activities	(383.8)	4,698.6	(409.6)
Effect of exchange rate changes on cash and cash equivalents	(8.5)	(0.1)	(16.0)
Change in cash and cash equivalents	(76.3)	140.0	4.2
Cash and cash equivalents at beginning of period	598.2	458.2	454.0
Cash and cash equivalents at end of period	$ 521.9	$ 598.2	$ 458.2