Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 113,943	$ 97,195
Trade accounts receivable, net of allowance for doubtful accounts of $97 and $283, respectively	82,913	66,714
Other accounts receivable	12,510	10,326
Prepaid expenses and other	18,251	16,645
Total current assets	227,617	190,880
Vessels, equipment, and other fixed assets at cost, net of accumulated depreciation of $318,403 and $282,395, respectively	1,187,292	1,191,280
Construction in progress	3,869	2,920
Goodwill	34,495	31,987
Intangibles, net of accumulated amortization of $8,650 and $7,208, respectively	25,949	27,390
Deferred costs and other assets	25,885	19,993
Total assets	1,505,107	1,464,450
Current liabilities:
Current portion of long-term debt	33,333	33,333
Accounts payable	21,146	15,130
Income and other taxes payable	5,019	4,066
Accrued personnel costs	22,387	23,417
Accrued interest expense	5,769	5,757
Other accrued liabilities	8,225	7,676
Total current liabilities	95,879	89,379
Long-term debt	286,463	293,095
Long-term income taxes:
Deferred tax liabilities	101,556	102,509
Other income taxes payable	17,233	19,400
Cash flow hedges	5,552	6,807
Other liabilities	11,269	7,303
Stockholders' equity:
Preferred stock, no par value; 2,000 authorized; no shares issued	0	0
Class A Common Stock, $0.01 par value; 60,000 shares authorized; 26,540 and 26,269 shares issued and 26,513 and 26,013 outstanding, respectively; Class B Common Stock $0.01 per value; 60,000 shares authorized; no shares issued	261	259
Additional paid-in capital	374,978	370,218
Retained earnings	548,592	536,468
Accumulated other comprehensive income	64,488	39,137
Treasury stock, at cost	(9,006)	(7,228)
Deferred compensation expense	7,842	7,103
Total stockholders' equity	987,155	945,957
Total liabilities and stockholders' equity	$ 1,505,107	$ 1,464,450