Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 31,431	$ 47,924
Short-term investments	30,000
Trade receivables, net of allowance for doubtful accounts of $2,928 and $3,040 (including related parties of $5,309 and $5,534)	61,037	66,399
Prepaid expenses and other current assets (including related parties of $274 and $274)	5,728	5,705
Total current assets	128,196	120,028
Property and equipment, net of accumulated depreciation of $200,310 and $198,282	56,312	57,874
Intangible assets subject to amortization, net of accumulated amortization of $80,002 and $78,234 (including related parties of $12,758 and $13,918)	14,889	16,656
Intangible assets not subject to amortization	220,701	220,701
Goodwill	50,081	50,081
Deferred income taxes	53,348	57,929
Other assets	1,738	1,693
Total assets	525,265	524,962
Current liabilities
Current maturities of long-term debt	3,750	3,750
Accounts payable and accrued expenses (including related parties of $4,019 and $3,791)	25,843	29,787
Total current liabilities	29,593	33,537
Long-term debt, less current maturities, net of unamortized debt issuance costs of $2,880 and $3,226	308,058	309,587
Other long-term liabilities	15,308	14,565
Total liabilities	352,959	357,689
Commitments and contingencies (note 4)
Stockholders' equity
Additional paid-in capital	907,820	910,228
Accumulated deficit	(730,863)	(738,849)
Accumulated other comprehensive income (loss)	(4,660)	(4,115)
Total stockholders' equity	172,306	167,273
Total liabilities and stockholders' equity	525,265	524,962
Class A common stock
Stockholders' equity
Common stock	6	6
Class B common stock
Stockholders' equity
Common stock	2	2
Class U common stock
Stockholders' equity
Common stock	$ 1	$ 1

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.