Commitments and Contingencies - Additional Information (Details) (USD $)	3 Months Ended	1 Months Ended
	Mar. 31, 2015	Aug. 31, 2013	Sep. 30, 2013 claim
Loss Contingencies [Line Items]
Agreement term to repurchase certain products shipped to distributor from date of shipment (after 90 days)	90 days
Pre-1972 Recording Matters [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Number of pending claims		3	1
Compensatory damages sought	100,000,000
Telephone Consumer Protection Act Suits [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Statutory damages sought per violation	500
Maximum [Member]
Loss Contingencies [Line Items]
Operating lease obligations, term	15 years
Maximum [Member] | Sound Exchange, Inc | Pending Litigation [Member]
Loss Contingencies [Line Items]
Compensatory damages sought		100,000,000
Maximum [Member] | Telephone Consumer Protection Act Suits [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Treble damages sought per willful violation	1,500
Minimum [Member]
Loss Contingencies [Line Items]
Operating lease obligations, term	1 year
Minimum [Member] | Sound Exchange, Inc | Pending Litigation [Member]
Loss Contingencies [Line Items]
Compensatory damages sought		50,000,000
XM-5, FM-5, FM-6, XM-3, and XM-4 [Member]
Loss Contingencies [Line Items]
Operating performance over design life	15 years
XM-4 [Member]
Loss Contingencies [Line Items]
Period beyond expected operating performance of design life for XM-4	5 years
XM-4 [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Additional payments required if XM-4 continues to operate above baseline specifications	10,000,000