Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 40,852	$ 31,610
Receivables:
Trade	60,218	60,037
Contractual third-party reclamation receivables	10,540	10,207
Other	2,968	3,220
Total receivables	73,726	73,464
Inventories	40,421	37,734
Other current assets	20,133	16,504
Total current assets	175,132	159,312
Property, plant and equipment:
Land and mineral rights	264,489	261,741
Plant and equipment	638,903	635,720
Gross property, plant and equipment	903,392	897,461
Less accumulated depreciation, depletion and amortization	399,344	384,621
Net property, plant and equipment	504,048	512,840
Advanced coal royalties	4,262	4,316
Reclamation deposits	73,100	72,718
Restricted investments and bond collateral	87,636	87,209
Contractual third-party reclamation receivables, less current portion	84,089	84,158
Intangible assets, net of accumulated amortization of $12.8 million and $12.4 million at March 31, 2013 and December 31, 2012, respectively	2,784	3,203
Other assets	11,964	12,359
Total Assets	943,015	936,115
Current liabilities:
Current installments of long-term debt	23,294	23,791
Accounts payable and accrued expenses:
Trade	57,294	52,093
Production taxes	38,154	33,228
Workers' compensation	815	820
Postretirement medical benefits	14,068	14,068
SERP	390	390
Deferred revenue	15,385	12,822
Asset retirement obligations	23,154	22,238
Other current liabilities	5,528	11,462
Total current liabilities	178,082	170,912
Long-term debt, less current installments	332,992	337,198
Workers' compensation, less current portion	8,524	8,710
Excess of black lung benefit obligation over trust assets	8,439	8,356
Postretirement medical benefits, less current portion	320,759	319,775
Pension and SERP obligations, less current portion	54,251	54,250
Deferred revenue, less current portion	54,488	56,891
Asset retirement obligations, less current portion	240,335	241,609
Intangible liabilities, net of accumulated amortization of $11.7 million and $11.4 million at March 31, 2013 and December 31, 2012, respectively	6,370	6,625
Other liabilities	25,305	18,020
Total liabilities	1,229,545	1,222,346
Shareholders' deficit:
Preferred stock of $1.00 par value Authorized 5,000,000 shares; Issued and outstanding 159,960 shares at March 31, 2013 and December 31, 2012	160	160
Common stock of $2.50 par value Authorized 30,000,000 shares; Issued and outstanding 14,365,363 shares at March 31, 2013 and 14,201,411 shares at December 31, 2012	35,912	35,502
Other paid-in capital	132,828	130,852
Accumulated other comprehensive loss	(146,603)	(148,345)
Accumulated deficit	(292,452)	(289,727)
Total Westmoreland Coal Company shareholders' deficit	(270,155)	(271,558)
Noncontrolling interest	(16,375)	(14,673)
Total deficit	(286,530)	(286,231)
Total Liabilities and Shareholders' Deficit	$ 943,015	$ 936,115

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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.