Goodwill and Other Intangible Assets (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Abstract]
Goodwill	$ 64,432,000	$ 65,829,000
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	9,300,000	8,900,000
Accumulated amortization	6,300,000	5,800,000
Acquired Finite-Lived Intangible Assets [Member]
Intangible assets, Finite-lived [Abstract]
Weighted average amortization period for acquired intangible assets subject to amortization (in years)	15 years
Amortization expense	600,000	600,000	800,000
Estimated amortization expense, 2014	400,000
Estimated amortization expense, 2015	400,000
Estimated amortization expense, 2016	400,000
Estimated amortization expense, 2017	300,000
Estimated amortization expense, 2018	300,000
Customer Contracts [Member]
Intangible assets, Finite-lived [Abstract]
Amortization expense	400,000	400,000	700,000
Estimated amortization expense, 2014	400,000
Estimated amortization expense, 2015	100,000
Estimated amortization expense, 2016	0
Finite-lived intangible assets, gross, non-current	500,000
Number of PCC satellite facilities	7
Finite-lived intangible assets, gross, current	400,000
Patents & Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	6,400,000	6,000,000
Accumulated amortization	3,700,000	3,400,000
Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	2,900,000	2,900,000
Accumulated amortization	$ 2,600,000	$ 2,400,000