The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Summary of Significant Accounting Policies - Customer Relationships and Acquisition Costs and Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amortizable intangible assets
Net Carrying Amount	$ 1,393,183	$ 1,506,522
Amortization	201,878	186,774	$ 116,093
Included in Depreciation and Amortization
Estimated amortization expense for existing intangible assets for the next five succeeding fiscal years
2020	160,865
2021	157,647
2022	127,148
2023	121,256
2024	116,253
Thereafter	712,369
Customer relationship intangible assets
Amortizable intangible assets
Gross Carrying Amount	1,751,848	1,718,919
Accumulated Amortization	(544,721)	(455,705)
Net Carrying Amount	$ 1,207,127	1,263,214
Customer relationship intangible assets \| Minimum
Amortizable intangible assets
Useful life of finite-lived intangible assets	10 years
Customer relationship intangible assets \| Maximum
Amortizable intangible assets
Useful life of finite-lived intangible assets	30 years
Customer relationship intangible assets \| Weighted Average
Amortizable intangible assets
Useful life of finite-lived intangible assets	17 years
Customer Inducements
Amortizable intangible assets
Useful life of finite-lived intangible assets	3 years
Gross Carrying Amount	$ 52,718	56,478
Accumulated Amortization	(29,397)	(34,181)
Net Carrying Amount	$ 23,321	22,297
Customer Inducements, Current Record Management Vendor Or Payments To Customers \| Minimum
Amortizable intangible assets
Useful life of finite-lived intangible assets	5 years
Customer Inducements, Current Record Management Vendor Or Payments To Customers \| Maximum
Amortizable intangible assets
Useful life of finite-lived intangible assets	15 years
Customer Inducements, Current Record Management Vendor Or Payments To Customers \| Weighted Average
Amortizable intangible assets
Useful life of finite-lived intangible assets	7 years
Data center in-place leases \| Weighted Average
Amortizable intangible assets
Remaining amortization period	5 years
Data center tenant relationships \| Weighted Average
Amortizable intangible assets
Remaining amortization period	8 years
Customer relationship and customer inducement intangible assets
Amortizable intangible assets
Amortization	$ 117,972	113,782	109,563
Data center in-place leases and tenant relationships
Amortizable intangible assets
Amortization	$ 46,696	43,061	0
Data Center Above Market Leases \| Weighted Average
Amortizable intangible assets
Remaining amortization period	4 years
Data Center Below Market Leases \| Weighted Average
Amortizable intangible assets
Remaining amortization period	9 years
Other Intangible Assets
Amortizable intangible assets
Gross Carrying Amount	$ 19,893	20,310
Accumulated Amortization	(18,405)	(14,798)
Net Carrying Amount	$ 1,488	5,512
Other Intangible Assets \| Weighted Average
Amortizable intangible assets
Useful life of finite-lived intangible assets	4 years
Data center lease-based intangible assets
Amortizable intangible assets
Gross Carrying Amount	$ 265,945	271,818
Accumulated Amortization	(103,210)	(50,807)
Net Carrying Amount	162,735	221,011
Gross Carrying Amount	12,750	12,318
Accumulated Amortization	(3,937)	(1,642)
Net Carrying Amount	8,813	10,676
Third-party commissions asset and other finite-lived intangible assets
Amortizable intangible assets
Gross Carrying Amount	31,708	30,071
Accumulated Amortization	(4,134)	(1,089)
Net Carrying Amount	27,574	28,982
Amortization	7,957	5,713	6,530
Permanent withdrawal fees
Amortizable intangible assets
Amortization	9,993	11,408	11,253
Permanent withdrawal fees \| Amortization Expense Charged To Revenues
Estimated amortization expense for existing intangible assets for the next five succeeding fiscal years
2020	7,760
2021	5,207
2022	3,200
2023	2,112
2024	1,125
Thereafter	1,303
Data center above-market leases and data center below-market leases
Amortizable intangible assets
Amortization	3,710	4,873	$ 0
Data center above-market leases and data center below-market leases \| Amortization Expense Charged To Revenues
Estimated amortization expense for existing intangible assets for the next five succeeding fiscal years
2020	872
2021	234
2022	273
2023	(470)
2024	(610)
Thereafter	(3,112)
Customer Relationships, Customer Inducements and Data Center
Amortizable intangible assets
Gross Carrying Amount	2,102,219	2,077,286
Accumulated Amortization	(681,462)	(541,782)
Net Carrying Amount	$ 1,420,757	$ 1,535,504