Satellite Network and Other Equipment - Summary of Satellite Network and Other Equipment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 162,509	$ 157,656
Less: accumulated depreciation and amortization	(25,965)	(24,628)
Property, plant and equipment, net	136,544	133,028
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	381	381
Satellite Network [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	29,814	29,362
Satellite Network [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	1 year
Satellite Network [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Capitalized Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,989	4,563
Capitalized Software [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Capitalized Software [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Computer Hardware [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Property, plant and equipment, gross	2,486	2,419
Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,370	2,125
Other [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Other [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Assets under Construction [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 122,469	$ 118,806