SHAREHOLDERS' EQUITY (DETAILS 2) (Common Stock [Member], USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 05, 2014
Treasury Shares [Line Items]
Value of share repurchase authorized by the Board of Directors during the period				$ 750,000,000
Total shares	11,752,000us-gaap_TreasuryStockSharesAcquired	10,830,000us-gaap_TreasuryStockSharesAcquired	9,376,000us-gaap_TreasuryStockSharesAcquired
Total cost	543,202,000	472,263,000	317,687,000
Average price per share	$ 46.22	$ 43.61	$ 33.88
In the open market [Member]
Treasury Shares [Line Items]
Total shares	11,317,000	7,362,000	6,057,000
Total cost	524,168,000	337,083,000	203,704,000
Average price per share	$ 46.32	$ 45.79	$ 33.63
From employees [Member]
Treasury Shares [Line Items]
Total shares	435,000	468,000	319,000
Total cost	19,034,000	19,080,000	10,483,000
Average price per share	$ 43.82	$ 40.75	$ 32.85
From founding shareholder [Member]
Treasury Shares [Line Items]
Total shares	0	3,000,000	3,000,000
Total cost	$ 0	$ 116,100,000	$ 103,500,000
Average price per share	$ 0.00	$ 38.70	$ 34.50
From founding shareholder [Member] \| Trident [Member]
Treasury Shares [Line Items]
Total shares		3,000,000	3,000,000

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Amount of stock repurchase plan authorized.

+ References

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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