Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Financial information relating to reporting segments
Sales of metal	$ 205,929		$ 230,593	$ 254,406	$ 204,564	$ 246,911		$ 343,575	$ 231,090	$ 199,624	$ 895,492		$ 1,021,200		$ 515,457
Production costs applicable to sales	(107,413)		(124,967)	(131,823)	(92,554)	(109,127)		(141,253)	(77,102)	(92,474)	(456,757)		(419,956)		(257,636)
Depreciation and depletion	(52,397)		(52,844)	(61,024)	(52,592)	(58,166)		(58,652)	(57,641)	(50,041)	(218,857)		(224,500)		(141,619)
Gross profit (loss)											219,878		376,744		116,202
Exploration expense	6,441		6,957	6,305	6,567	7,517		4,772	4,077	2,762	26,270		19,128		14,249
Loss on impairment											5,825		0		0
Other operating expenses	5,883		11,836	13,680	8,664	10,577		11,507	12,931	15,805
OPERATING INCOME											153,545		306,796		74,900
Interest and other income											14,436		(6,610)		771
Interest expense, net											(26,169)		(34,774)		(30,942)
Loss on debt extinguishments											(1,036)		(5,526)		(20,300)
Fair value adjustments, net											(23,487)		(52,050)		(117,094)
Income tax benefit (expense)											(68,612)		(114,337)		9,481
Income (loss) from continuing operations	37,550		(15,821)	22,973	3,975	11,364		31,060	38,611	12,464	48,677		93,499		(83,184)
Income (Loss) from discontinued operations											0		0		(6,029)
Gain (loss) on sale of net assets of discontinued operations											0		0		(2,095)
Net income	37,550		(15,821)	22,973	3,975	11,364		31,060	38,611	12,464	48,677		93,499		(91,308)
Segment assets	2,974,056					2,963,130					2,974,056		2,963,130		3,000,389
Capital expenditures	21,784		29,972	32,238	31,647	40,207		38,099	25,764	15,918	115,641		119,988		155,994
Palmarejo [Member]
Financial information relating to reporting segments
Sales of metal											442,098		513,097		230,024
Production costs applicable to sales											(197,478)		(186,201)		(127,658)
Depreciation and depletion											(146,595)		(159,264)		(91,505)
Gross profit (loss)											98,025		167,632		10,861
Exploration expense											7,575		6,863		4,658
Loss on impairment											0
Other operating expenses											11		949		352
OPERATING INCOME											90,439		159,820		5,851
Interest and other income											4,017		(9,099)		914
Interest expense, net											(18,938)		(23,453)		(21,567)
Loss on debt extinguishments											0		0
Fair value adjustments, net											(31,054)		(40,046)		(98,707)
Income tax benefit (expense)											(18,066)		(28,023)		16,901
Income (loss) from continuing operations															(96,608)
Net income											26,398		59,199		(96,608)
Segment assets	1,905,269	[1]				2,029,769	[1]				1,905,269	[1]	2,029,769	[1]	2,119,367	[1]
Capital expenditures											38,456	[2]	36,976	[2]	54,226	[2]
San Bartolome [Member]
Financial information relating to reporting segments
Sales of metal											178,005		267,502		142,989
Production costs applicable to sales											(71,428)		(79,679)		(60,023)
Depreciation and depletion											(16,709)		(22,410)		(19,650)
Gross profit (loss)											89,868		165,413		63,316
Exploration expense											159		248		9
Loss on impairment											0
Other operating expenses											80		342
OPERATING INCOME											89,629		164,823		63,307
Interest and other income											9,719		156		(373)
Interest expense, net											(72)		(45)		325
Loss on debt extinguishments											0		0
Fair value adjustments, net											0		0
Income tax benefit (expense)											(44,632)		(59,867)		(21,655)
Income (loss) from continuing operations															40,954
Net income											54,644		105,067		40,954
Segment assets	302,922	[1]				276,423	[1]				302,922	[1]	276,423	[1]	260,653	[1]
Capital expenditures											25,672	[2]	17,731	[2]	6,159	[2]
Kensington [Member]
Financial information relating to reporting segments
Sales of metal											110,987		151,186		23,628
Production costs applicable to sales											(87,089)		(101,672)		(14,043)
Depreciation and depletion											(41,645)		(35,839)		(17,487)
Gross profit (loss)											(17,747)		13,675		(7,902)
Exploration expense											3,283		1,102		659
Loss on impairment											0
Other operating expenses											74		317		170
OPERATING INCOME											(21,104)		12,256		(8,731)
Interest and other income											(77)		4		(26)
Interest expense, net											(2,972)		(4,889)		1,591
Loss on debt extinguishments											(1,036)		0
Fair value adjustments, net											4,089		(8,438)		(13,783)
Income tax benefit (expense)											0		(31)		(8)
Income (loss) from continuing operations															(24,139)
Net income											(21,100)		(1,098)		(24,139)
Segment assets	508,658	[1]				507,891	[1]				508,658	[1]	507,891	[1]	512,401	[1]
Capital expenditures											36,994	[2]	34,013	[2]	92,730	[2]
Rochester [Member]
Financial information relating to reporting segments
Sales of metal											132,392		57,331		54,323
Production costs applicable to sales											(74,256)		(28,257)		(24,760)
Depreciation and depletion											(8,065)		(2,824)		(1,890)
Gross profit (loss)											50,071		26,250		27,673
Exploration expense											3,591		1,989		190
Loss on impairment											0
Other operating expenses											1,401		19,931		1,544
OPERATING INCOME											45,079		4,330		25,939
Interest and other income											358		57		681
Interest expense, net											(26)		(21)
Loss on debt extinguishments											0		0
Fair value adjustments, net											0		0
Income tax benefit (expense)											0		0
Income (loss) from continuing operations															26,620
Net income											45,411		4,366		26,620
Segment assets	104,373	[1]				76,852	[1]				104,373	[1]	76,852	[1]	29,734	[1]
Capital expenditures											11,794	[2]	27,217	[2]	2,349	[2]
Martha [Member]
Financial information relating to reporting segments
Sales of metal											13,162		13,347		53,875
Production costs applicable to sales											(17,682)		(15,513)		(27,040)
Depreciation and depletion											(692)		(556)		(8,525)
Gross profit (loss)											(5,212)		(2,722)		18,310
Exploration expense											8,648		6,367		5,791
Loss on impairment											5,825
Other operating expenses											2,108		156
OPERATING INCOME											(21,793)		(9,245)		12,519
Interest and other income											(1,153)		(544)		(3,974)
Interest expense, net											(3)		(458)		90
Loss on debt extinguishments											0		0
Fair value adjustments, net											0		0
Income tax benefit (expense)											976		(1,219)		(8,523)
Income (loss) from continuing operations															(68)
Net income											(21,973)		(11,466)		(68)
Segment assets	9,813	[1]				19,717	[1]				9,813	[1]	19,717	[1]	21,290	[1]
Capital expenditures											1,193	[2]	3,426	[2]	100	[2]
Endeavor [Member]
Financial information relating to reporting segments
Sales of metal											18,848		18,737		10,618
Production costs applicable to sales											(8,824)		(8,634)		(4,112)
Depreciation and depletion											(4,591)		(3,148)		(1,989)
Gross profit (loss)											5,433		6,955		4,517
Exploration expense											0		0
Loss on impairment											0
Other operating expenses											0		(1)
OPERATING INCOME											5,433		6,956		4,517
Interest and other income											0		0
Interest expense, net											0		0
Loss on debt extinguishments											0		0
Fair value adjustments, net											0		0
Income tax benefit (expense)											409		0
Income (loss) from continuing operations															4,517
Net income											5,842		6,956		4,517
Segment assets	31,479	[1]				35,686	[1]				31,479	[1]	35,686	[1]	39,530	[1]
Capital expenditures											0	[2]	0	[2]
Other Mining Properties [Member]
Financial information relating to reporting segments
Sales of metal											0		0
Production costs applicable to sales											0		0
Depreciation and depletion											(560)		(459)		(573)
Gross profit (loss)											(560)		(459)		(573)
Exploration expense											3,014		2,559		2,942
Loss on impairment											0
Other operating expenses											30,564		29,126		24,987
OPERATING INCOME											(34,138)		(32,144)		(28,502)
Interest and other income											1,572		2,816		3,549
Interest expense, net											(4,158)		(5,908)		(7,369)
Loss on debt extinguishments											0		(5,526)		(20,300)
Fair value adjustments, net											3,478		(3,566)		(4,604)
Income tax benefit (expense)											(7,299)		(25,197)		22,766
Income (loss) from continuing operations															(34,460)
Income (Loss) from discontinued operations															(6,029)
Gain (loss) on sale of net assets of discontinued operations															(2,095)
Net income											(40,545)		(69,525)		(42,584)
Segment assets	111,542	[1]				16,792	[1]				111,542	[1]	16,792	[1]	17,414	[1]
Capital expenditures											1,532	[2]	625	[2]	430	[2]
Total [Member]
Financial information relating to reporting segments
Sales of metal											895,492		1,021,200		515,457
Production costs applicable to sales											(456,757)		(419,956)		(257,636)
Depreciation and depletion											(218,857)		(224,500)		(141,619)
Gross profit (loss)											219,878		376,744
Exploration expense											26,270		19,128		14,249
Loss on impairment											5,825
Other operating expenses											34,238		50,820		27,053
OPERATING INCOME											153,545		306,796
Interest and other income											14,436		(6,610)		771
Interest expense, net											(26,169)		(34,774)		(30,942)
Loss on debt extinguishments											(1,036)		(5,526)		(20,300)
Fair value adjustments, net											(23,487)		(52,050)		(117,094)
Income tax benefit (expense)											(68,612)		(114,337)		9,481
Income (loss) from continuing operations															(83,184)
Income (Loss) from discontinued operations															(6,029)
Gain (loss) on sale of net assets of discontinued operations															(2,095)
Net income											48,677		93,499		(91,308)
Segment assets	2,974,056	[1]				2,963,130	[1]				2,974,056	[1]	2,963,130	[1]	3,000,389	[1]
Capital expenditures											$ 115,641	[2]	$ 119,988	[2]	$ 155,994	[2]

[1] Segment assets consist of receivables, prepaids, inventories, property, plant and equipment, and mining properties

[2] Balance represents cash flow amounts