Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Property and equipment useful life

Depreciation is calculated using the straight-line method, over the estimated useful lives of the following assets:

	Estimated Useful Life (years)
Computers, equipment, and software	1.5 to 7
Furniture and fixtures	5 to 7
Building and building improvements	7 to 40
Land improvements	10 to 40
Leasehold improvements	Lease term, not to exceed 10 years

Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]

The cumulative effect of the adjustments made to the Company's 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	)