Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 31,610	$ 30,783
Receivables:
Trade	60,037	46,235
Contractual third-party reclamation receivables	10,207	11,259
Other	3,220	3,493
Total receivables	73,464	60,987
Inventories	37,734	25,696
Other current assets	16,504	4,987
Total current assets	159,312	122,453
Property, plant and equipment:
Land and mineral rights	261,741	198,201
Plant and equipment	635,720	527,127
Gross property, plant and equipment	897,461	725,328
Less accumulated depreciation, depletion and amortization	384,621	328,596
Net property, plant and equipment	512,840	396,732
Advanced coal royalties	4,316	2,552
Reclamation deposits	72,718	71,939
Restricted investments and bond collateral	87,209	58,305
Contractual third-party reclamation receivables, less current portion	84,158	87,674
Intangible assets, net of accumulated amortization of $12.4 million and $10.7 million at December 31, 2012 and December 31, 2011, respectively	3,203	4,879
Other assets	12,359	14,638
Total Assets	936,115	759,172
Current liabilities:
Current installments of long-term debt	23,791	20,795
Accounts payable and accrued expenses:
Trade	52,093	45,326
Production taxes	33,228	25,605
Workers' compensation	820	911
Postretirement medical benefits	14,068	13,179
SERP	390	391
Deferred revenue	12,822	9,852
Asset retirement obligations	22,238	19,765
Other current liabilities	11,462	8,298
Total current liabilities	170,912	144,122
Long-term debt, less current installments	337,198	261,474
Workers' compensation, less current portion	8,710	10,715
Excess of pneumoconiosis benefit obligation over trust assets	8,356	6,565
Postretirement medical benefits, less current portion	319,775	245,462
Pension and SERP obligations, less current portion	54,250	28,991
Deferred revenue, less current portion	56,891	65,834
Asset retirement obligations, less current portion	241,609	227,713
Intangible liabilities, net of accumulated amortization $11.4 million at December 31, 2012 and $10.4 million at December 31, 2011, respectively	6,625	7,644
Other liabilities	18,020	10,510
Total liabilities	1,222,346	1,009,030
Shareholders' deficit:
Preferred stock of $1.00 par value Authorized 5,000,000 shares; Issued and outstanding 159,960 shares at December 31, 2012, and 159,960 shares at December 31, 2011, respectively	160	160
Common stock of $2.50 par value Authorized 30,000,000 shares; Issued and outstanding 14,201,411 shares at December 31, 2012, and 13,811,379 shares at December 31, 2011, respectively	35,502	34,527
Other paid-in capital	130,852	126,288
Accumulated other comprehensive loss	(148,345)	(121,455)
Accumulated deficit	(289,727)	(281,141)
Total Westmoreland Coal Company shareholders' deficit	(271,558)	(241,621)
Noncontrolling interest	(14,673)	(8,237)
Total deficit	(286,231)	(249,858)
Total Liabilities and Shareholders' Deficit	$ 936,115	$ 759,172

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, and other costs not separately disclosed in the balance sheet that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered.