Unaudited Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 38,177	$ 185,175
Trade accounts receivable, net of allowance for doubtful accounts of $304 and $3,250, respectively	107,393	85,706
Other accounts receivable	10,162	8,506
Prepaid expenses and other current assets	22,919	25,186
Total current assets	178,651	304,573
Vessels, equipment, and other fixed assets at cost, net of accumulated depreciation of $401,830 and $389,469, respectively	1,281,217	1,136,360
Construction in progress	172,531	169,429
Goodwill	31,000	33,438
Intangibles, net of accumulated amortization of $15,137 and $12,975, respectively	19,461	21,624
Cash held in escrow	19,624	47,028
Deferred costs and other assets	32,440	33,222
Total assets	1,734,924	1,745,674
Current liabilities:
Accounts payable	21,234	29,089
Income and other taxes payable	4,752	6,262
Accrued personnel costs	21,389	23,656
Accrued interest expense	1,917	9,327
Other accrued liabilities	11,496	11,402
Total current liabilities	60,788	79,736
Long-term debt	500,898	500,999
Long-term income taxes:
Deferred tax liabilities	107,821	105,867
Other income taxes payable	23,445	23,665
Other liabilities	6,478	7,525
Stockholders' equity:
Class A Common Stock, $0.01 par value; 60,000 shares authorized; 26,811 and 26,941 shares issued and 27,164 and 26,906 outstanding, respectively; Class B Common Stock $0.01 per value; 60,000 shares authorized; no shares issued	269	266
Additional paid-in capital	398,540	389,881
Retained earnings	604,260	579,062
Accumulated other comprehensive income	44,986	59,875
Treasury stock, at cost	(20,121)	(11,533)
Deferred compensation expense	7,560	10,331
Total stockholders' equity	1,035,494	1,027,882
Total liabilities and stockholders' equity	$ 1,734,924	$ 1,745,674