Unaudited Condensed Consolidated Balance Sheets - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 78,390,000	$ 50,785,000
Trade accounts receivable, net of allowance for doubtful accounts of $1,477 and $2,506, respectively	70,634,000	88,721,000
Other accounts receivable	8,158,000	9,410,000
Prepaid expenses and other current assets	21,057,000	17,825,000
Total current assets	178,239,000	166,741,000
Vessels, equipment, and other fixed assets at cost, net of accumulated depreciation of $461,485 and $428,538, respectively	1,369,451,000	1,356,839,000
Construction in progress	90,799,000	127,722,000
Goodwill	23,755,000	25,010,000
Intangibles, net of accumulated amortization of $20,182 and $18,741, respectively	$ 14,416,000	15,858,000
Cash held in escrow		3,683,000
Deferred costs and other assets	$ 20,131,000	20,502,000
Total assets	1,696,791,000	1,716,355,000
Current liabilities:
Accounts payable	13,010,000	22,494,000
Income and other taxes payable	6,174,000	4,578,000
Accrued personnel costs	14,617,000	20,403,000
Accrued interest expense	9,649,000	9,610,000
Other accrued liabilities	6,888,000	10,338,000
Total current liabilities	50,338,000	67,423,000
Long-term debt	572,669,000	544,732,000
Long-term income taxes:
Deferred tax liabilities	93,603,000	104,346,000
Other income taxes payable	25,378,000	24,730,000
Other liabilities	6,127,000	6,371,000
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; 27,934 and 27,361 shares issued and 25,706 and 25,114 outstanding, respectively; Class B Common Stock $0.01 par value; 60,000 shares authorized; no shares issued	272,000	271,000
Additional paid-in capital	414,751,000	410,641,000
Retained earnings	646,043,000	659,403,000
Accumulated other comprehensive income	(43,042,000)	(30,665,000)
Treasury stock, at cost	(77,792,000)	(78,441,000)
Deferred compensation expense	8,444,000	7,544,000
Total stockholders' equity	948,676,000	968,753,000
Total liabilities and stockholders' equity	$ 1,696,791,000	$ 1,716,355,000