Acquisitions - Preliminary Purchase Price Allocation (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Aug. 01, 2016	Jan. 15, 2016	Dec. 31, 2015	Nov. 02, 2015
Business Acquisition [Line Items]
Assets held for sale	$ 96,923			$ 33,257
Goodwill	3,118,686			1,063,200
Liabilities held for sale	$ (14,660)			$ (3,535)
Telecity Group plc
Business Acquisition [Line Items]
Cash and cash equivalents			$ 73,368
Accounts receivable			24,042
Other current assets			41,079
Assets held for sale			867,917
Property, plant and equipment			1,058,583
Goodwill			2,216,173
Intangible assets			704,014
Deferred tax assets			1,198
Other assets			4,124
Total assets acquired			4,990,498
Accounts payable and accrued expenses			(90,589)
Accrued property, plant and equipment			(3,634)
Other current liabilities			(27,259)
Liabilities held for sale			(156,171)
Capital lease and other financing obligations			(162,359)
Mortgage and loans payable			(592,304)
Deferred tax liabilities			(177,715)
Other liabilities			(35,581)
Net assets acquired			$ 3,744,886
Digital Realty
Business Acquisition [Line Items]
Cash and cash equivalents		$ 4,073
Accounts receivable		1,507
Other current assets		794
Property, plant and equipment		138,568
Goodwill		45,187
Intangible assets		11,758
Other assets		82
Total assets acquired		201,969
Accounts payable and accrued expenses		(2,044)
Other current liabilities		(2,798)
Deferred tax liabilities		(32,687)
Other liabilities		(790)
Net assets acquired		$ 163,650
Bit-isle
Business Acquisition [Line Items]
Cash and cash equivalents					$ 33,198
Accounts receivable					7,359
Other current assets					51,038
Long-term investments					3,806
Property, plant and equipment					308,985
Goodwill					95,444
Intangible assets					111,374
Other assets					22,981
Total assets acquired					634,185
Accounts payable and accrued expenses					(15,028)
Accrued property, plant and equipment					(465)
Other current liabilities					(8,689)
Capital lease and other financing obligations					(108,833)
Mortgage and loans payable					(190,227)
Deferred tax liabilities					(32,192)
Other liabilities					(3,384)
Net assets acquired					$ 275,367