CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current Assets
Cash and Cash Equivalents	$ 100,736	$ 65,675
Accounts Receivables, net	16,412us-gaap_AccountsAndNotesReceivableNet	18,801us-gaap_AccountsAndNotesReceivableNet
Prepaid Expenses	5,513us-gaap_PrepaidExpenseCurrent	5,436us-gaap_PrepaidExpenseCurrent
Inventory	22,223us-gaap_InventoryNet	24,281us-gaap_InventoryNet
Voyages in Progress	29,586us-gaap_UnbilledReceivablesCurrent	14,953us-gaap_UnbilledReceivablesCurrent
Other Current Assets	2,029us-gaap_OtherAssetsCurrent	2,251us-gaap_OtherAssetsCurrent
Total Current Assets	176,499us-gaap_AssetsCurrent	131,396us-gaap_AssetsCurrent
Non-Current Assets
Vessels, Net	909,992nat_VesselsNet	911,429nat_VesselsNet
Goodwill	18,979us-gaap_Goodwill	18,979us-gaap_Goodwill
Investment in Nordic American Offshore Ltd	55,223	64,128
Other Non-current Assets	8,331us-gaap_OtherAssetsNoncurrent	10,504us-gaap_OtherAssetsNoncurrent
Total Non-current Assets	992,525us-gaap_AssetsNoncurrent	1,005,041us-gaap_AssetsNoncurrent
Total Assets	1,169,024us-gaap_Assets	1,136,437us-gaap_Assets
Current Liabilities
Accounts Payable	6,664us-gaap_AccountsPayableCurrent	6,447us-gaap_AccountsPayableCurrent
Accrued Voyage Expenses	8,784nat_AccruedVoyageExpensesCurrent	6,249nat_AccruedVoyageExpensesCurrent
Accrued Liabilities	8,587us-gaap_AccruedLiabilitiesCurrent	6,567us-gaap_AccruedLiabilitiesCurrent
Total Current Liabilities	24,035us-gaap_LiabilitiesCurrent	19,263us-gaap_LiabilitiesCurrent
Long Term Debt	250,000us-gaap_LongTermDebtNoncurrent	250,000us-gaap_LongTermDebtNoncurrent
Deferred Tax Liability	0	37
Deferred Compensation Liability	12,914	12,154
Total Liabilities	286,949us-gaap_Liabilities	281,453us-gaap_Liabilities
Commitment and Contingencies
Shareholders' Equity
Common Stock, Par Value $0.01 per Share 180,000,000 and 90,000,000 authorized, 89,182,001 and 75,382,001 shares issued and outstanding at December 31, 2014 and December 31, 2013, respectively	892us-gaap_CommonStockValue	754us-gaap_CommonStockValue
Additional Paid-in Capital	114,291	208,240
Contributed Surplus	787,732nat_ContributedSurplus	751,567nat_ContributedSurplus
Accumulated Other Comprehensive Income	(8,032)	(160)
Accumulated Deficit	(12,808)	(105,417)
Total Shareholders' Equity	882,075us-gaap_StockholdersEquity	854,984us-gaap_StockholdersEquity
Total Liabilities and Shareholders' Equity	$ 1,169,024	$ 1,136,437

Carrying value as of the balance sheet date of obligations incurred through that date and payable related to the entity's voyage expenses. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

No definition available.