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FAIR VALUE (Details) (USD $) | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended
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Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Estimated Fair Value [Member] | Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Estimated Fair Value [Member] | Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 1 [Member] | Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 1 [Member] | Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member] | Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member] | Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member] | Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Estimated Fair Value [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Estimated Fair Value [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Estimated Fair Value [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Estimated Fair Value [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Total Gains (Losses) [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Total Gains (Losses) [Member] | Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member] Total Gains (Losses) [Member] | Sep. 30, 2010 Fair Value, Measurements, Nonrecurring [Member] Total Gains (Losses) [Member]
Investment securities available-for-sale: [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury securities |  |  |  |  | $ 20,761,000 | $ 20,454,000 | $ 20,761,000 | $ 20,454,000 | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agency and U.S. Government sponsored enterprise debt securities |  |  |  |  | 642,951,000 | 1,333,465,000 | 0 | 0 | 642,951,000 | 1,333,465,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agency and U.S. Government sponsored enterprise mortgage-backed securities: [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commercial mortgage-backed securities |  |  |  |  | 16,823,000 | 19,132,000 | 0 | 0 | 16,823,000 | 19,132,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential mortgage-backed securities |  |  |  |  | 1,093,829,000 | 306,714,000 | 0 | 0 | 1,093,829,000 | 306,714,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Municipal securities |  |  |  |  | 77,466,000 | 0 | 0 | 0 | 77,466,000 | 0 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other residential mortgage-backed securities: [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment grade |  |  |  |  | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-investment grade |  |  |  |  | 0 | 6,254,000 | 0 | 0 | 0 | 0 | 0 | 6,254,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate debt securities: [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment grade |  |  |  |  | 1,403,432,000 | 1,056,867,000 | 0 | 0 | 1,403,432,000 | 1,056,867,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-investment grade |  |  |  |  | 14,195,000 | 38,730,000 | 0 | 0 | 11,840,000 | 35,957,000 | 2,355,000 | 2,773,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other securities |  |  |  |  | 10,135,000 | 94,325,000 | 0 | 0 | 10,135,000 | 94,325,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total investment securities available-for-sale |  |  |  |  | 3,279,592,000 | 2,875,941,000 | 20,761,000 | 20,454,000 | 3,256,476,000 | 2,846,460,000 | 2,355,000 | 9,027,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity swap agreements |  |  |  |  | 200,000 | 206,000 | 0 | 0 | 200,000 | 206,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Foreign exchange options |  |  |  |  | 4,392,000 | 5,084,000 | 0 | 0 | 4,392,000 | 5,084,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate swaps |  |  |  |  | 17,791,000 | 13,000 | 0 | 0 | 17,791,000 | 13,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative liabilities |  |  |  |  | (20,206,000) | (3,463,000) | 0 | 0 | (17,237,000) | (14,000) | (2,969,000) | (3,449,000) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-covered impaired loans: [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total residential |  |  |  |  |  |  |  |  |  |  |  |  | 9,637,000 |  | 2,694,000 |  | 12,533,000 |  | 5,953,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 9,637,000 |  | 2,694,000 |  | 12,533,000 |  | 5,953,000 |  | (3,142,000) |  | (772,000) |  | (3,727,000) |  | (2,234,000) |
Total commercial real estate |  |  |  |  |  |  |  |  |  |  |  |  | 40,997,000 |  | 41,212,000 |  | 44,840,000 |  | 74,630,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 40,997,000 |  | 41,212,000 |  | 44,840,000 |  | 74,630,000 |  | (16,645,000) |  | (16,046,000) |  | (34,192,000) |  | (36,230,000) |
Total commercial and industrial |  |  |  |  |  |  |  |  |  |  |  |  | 4,405,000 |  | 7,830,000 |  | 5,513,000 |  | 7,925,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 4,405,000 |  | 7,830,000 |  | 5,513,000 |  | 7,925,000 |  | (6,328,000) |  | (3,053,000) |  | (9,915,000) |  | (4,836,000) |
Total consumer |  |  |  |  |  |  |  |  |  |  |  |  | 315,000 |  | 167,000 |  | 359,000 |  | 166,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 315,000 |  | 167,000 |  | 359,000 |  | 166,000 |  | (265,000) |  | 96,000 |  | (443,000) |  | (245,000) |
Total non-covered impaired loans |  |  |  |  |  |  |  |  |  |  |  |  | 55,354,000 |  | 51,903,000 |  | 63,245,000 |  | 88,674,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 55,354,000 |  | 51,903,000 |  | 63,245,000 |  | 88,674,000 |  | (26,380,000) |  | (19,775,000) |  | (48,277,000) |  | (43,545,000) |
Mortgage servicing assets (single-family, multifamily and commercial) |  |  |  |  |  |  |  |  |  |  |  |  | 12,495,000 |  | 15,973,000 |  | 12,495,000 |  | 15,973,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 12,495,000 |  | 15,973,000 |  | 12,495,000 |  | 15,973,000 |  | (212,000) |  | (284,000) |  | (675,000) |  | (348,000) |
Non-covered OREO |  |  | 21,200,000 |  |  |  |  |  |  |  |  |  | 36,000 |  | 2,574,000 |  | 13,692,000 |  | 4,101,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 36,000 |  | 2,574,000 |  | 13,692,000 |  | 4,101,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | (17,000) |  | (1,099,000) |  | (1,529,000) |  | (4,012,000) |
Covered OREO |  |  | 87,300,000 |  |  |  |  |  |  |  |  |  | 18,068,000 | [1] | 27,205,000 | [1] | 110,133,000 | [2] | 57,234,000 | [2] | 0 | [1] | 0 | [1] | 0 | [2] | 0 | [2] | 18,068,000 | [1] | 27,205,000 | [1] | 110,133,000 | [2] | 57,234,000 | [2] | 0 | [1] | 0 | [1] | 0 | [2] | 0 | [2] | (3,252,000) | [1] | (6,569,000) | [1] | (18,655,000) | [2] | (32,496,000) | [2]
Loans held for sale |  |  |  |  |  |  |  |  |  |  |  |  | 2,714,000 |  | 359,000 |  | 2,714,000 |  | 3,737,000 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 0 |  | 2,714,000 |  | 359,000 |  | 2,714,000 |  | 3,737,000 |  | (260,000) |  | (228,000) |  | (260,000) |  | (2,059,000) |
FDIC percentage of reimbursement under shared loss agreements (in hundredths) | 80.00% | 80.00% | 80.00% | 80.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of company's liability for losses under shared loss agreements (in hundredths) | 20.00% | 20.00% | 20.00% | 20.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company's liability for losses under shared loss agreements | 650,000 | 1,300,000 | 3,700,000 | 6,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total eligible losses subject to shared loss agreements | $ 3,300,000 | $ 6,600,000 | $ 18,700,000 | $ 32,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company's liability for losses is 20% of the $3.3 million in losses, or $650 thousand, and 20% of the $6.6 million in losses, or $1.3 million, for the three months ended September 30, 2011 and 2010, respectively.
[2] | Covered OREO results from the WFIB and UCB FDIC-assisted acquisitions for which the Company entered into shared-loss agreements with the FDIC whereby the FDIC will reimburse the Company for 80% of eligible losses. As such, the Company's liability for losses is 20% of the $18.7 million in losses, or $3.7 million, and 20% of the $32.5 million in losses, or $6.5 million, for the nine months ended September 30, 2011 and 2010, respectively.

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale investment grade corporate debt securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale non-investment grade corporate debt securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale municipal securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale investment grade residential mortgage-backed securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale non-investment grade residential mortgage-backed securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale securities other than those separately disclosed. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale U.S. government agency and U.S. government sponsored enterprise debt securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale U.S. government agency and U.S. government sponsored enterprise commercial mortgage-backed securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale U.S. government agency and U.S. government sponsored enterprise residential mortgage-backed securities. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents available-for-sale U.S. Treasury securities. + Details
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- Definition The company's liability for eligible losses under shared-loss agreements. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the total of all covered other real estate owned resulting from acquisitions for which the company entered into shared-loss agreements. + Details
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- Definition Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as equity swap agreements. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents interest rate swap contracts entered into and existing as of the balance sheet date. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. This item represents loans held-for-sale as presented on the statement of financial position which may include mortgage loans held-for-sale, finance receivables held-for-sale, or any other loans classified as held-for-sale which are due the Company as of the balance sheet date. + Details
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- Definition Fair value as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents non-covered impaired loans receivable related to commercial and industrial real estate with loss recognized in earnings In current period. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents non-covered impaired loans receivable related to commercial real estate with loss recognized in earnings In current period. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents all non-covered impaired consumer loans receivable with loss recognized in earnings In current period. + Details
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Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
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Period Type: | duration

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents non-covered impaired loans receivable related to residential real estate with loss recognized in earnings In current period. + Details
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- Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the total of all non-covered impaired loans receivable with loss recognized in earnings In current period. + Details
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Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
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Period Type: | duration

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the total of all non-covered other real estate owned. + Details
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Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition The percentage of losses related to other real estate owned for which the company retains liability. + Details
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Namespace Prefix: | ewbc
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition The percentage of future losses on the OREO that the FDIC will absorb under the shared-loss agreements. + Details
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Namespace Prefix: | ewbc
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition The total eligible losses subject to reimbursement under shared-loss agreements. + Details
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Namespace Prefix: | ewbc
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 12 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 10 -Subparagraph i -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 6 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 15 -Paragraph 83 -URI http://asc.fasb.org/extlink&oid=6913464&loc=d3e34841-113949 + Details
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Balance Type: | credit
Period Type: | instant

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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents contracts related to the exchange of different currencies, including foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into and existing as of the balance sheet date. + Details
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Namespace Prefix: | us-gaap
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant