Sirius XM Holdings Inc. Annual report pursuant to Section 13 and 15(d)

Composition of Certain Financial Statement Captions - Schedule of property and equipment (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 78,098us-gaap_PropertyPlantAndEquipmentGross	$ 56,671us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation and amortization	(35,177)	(21,520)
Total property and equipment, net	42,921us-gaap_PropertyPlantAndEquipmentNet	35,151us-gaap_PropertyPlantAndEquipmentNet
Servers, computers and other related equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	39,890	27,361
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	25,893	11,314
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	2,721	2,248
Construction in progress
Property, Plant and Equipment [Line Items]
Total property and equipment	5,075	13,575
Software developed for internal use
Property, Plant and Equipment [Line Items]
Total property and equipment	4,519	2,173
Less accumulated depreciation and amortization	$ (1,700)	$ (700)