Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 104,936	$ 79,915
Trade accounts receivable, net of allowance of $1,575 and $2,032, respectively	158,867	247,069
Accounts receivable - related parties	39	161
Income tax receivable	1,330	3,121
Inventories	39,769	44,557
Prepaid expenses	16,060	15,779
Other current assets	9,732	9,934
Deferred tax assets	15,514	14,664
Total current assets	346,247	415,200
Property and equipment, net	982,153	1,007,969
Deferred debt costs, net of amortization	14,639	15,350
Goodwill	78,011	78,011
Other intangible assets, net of amortization	69,001	71,173
Other assets	9,499	9,474
Total assets	1,499,550	1,597,177
Current liabilities:
Accounts payable	33,715	50,618
Accrued expenses	65,642	90,810
Current portion of long-term debt	46,816	48,575
Other current liabilities	4,753	6,135
Total current liabilities	150,926	196,138
Long-term debt, net of unamortized premium on notes of $1,155 and $1,217, respectively	878,219	882,572
Deferred tax liabilities	133,354	147,621
Other long-term liabilities	29,587	28,193
Commitments and contingencies
Stockholders' equity:
Preferred stock; $0.01 par value; 5,000,000 shares authorized; none designated or issued at March 31, 2015 and December 31, 2014
Common stock; $0.01 par value; 80,000,000 shares authorized; 43,500,032 shares issued and 42,643,875 shares outstanding at March 31, 2015; 43,500,032 shares issued and 42,241,719 shares outstanding at December 31, 2014	435	435
Additional paid-in capital	365,482	369,920
Retained deficit	(47,691)	(15,067)
Treasury stock, at cost, 856,157 and 1,258,313 shares at March 31, 2015 and December 31, 2014, respectively	(10,762)	(12,635)
Total stockholders' equity	307,464	342,653
Total liabilities and stockholders' equity	$ 1,499,550	$ 1,597,177