Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Schedule of new accounting pronouncements and changes in accounting principles

The cumulative effect of the adjustments made to the Company's Condensed Consolidated Balance Sheet as of the adoption date is detailed as follows (in millions):

	December 31, 2018						January 1, 2019
	As reported			Adjustments due to ASC 842			As adjusted
Assets:
Prepaid expenses and other current assets	$	268.1		$	(1.4	)	$	266.7
Property and equipment, net	951.7			(42.9		)	908.8
Operating lease assets	—			192.5			192.5
Other long-term assets	403.5			1.3			404.8
Total assets	$	9,363.3		$	149.5		$	9,512.8
Liabilities:
Other accrued liabilities	$	233.5		$	35.6		$	269.1
Long-term operating lease liabilities	—			185.5			185.5
Other long-term liabilities	119.8			(66.7		)	53.1
Total liabilities	$	4,540.1		$	154.4		$	4,694.5
Stockholders' equity:
Accumulated deficit	$	(2,831.4	)	$	(4.9	)	$	(2,836.3	)