Consolidated Statements Of Changes In Equity (USD $) In Thousands | Common Stock [Member] | Retained Earnings [Member] | Accumulated Other Comprehensive Income [Member] | Total Shareholders' Equity [Member] | Noncontrolling Interests [Member] | Total |
|---|---|---|---|---|---|---|
| Balance at Dec. 31, 2009 | $ 872,876 | $ 1,514,398 | $ 387,086 | $ 2,774,360 | $ 17,354 | $ 2,791,714 |
| Net income | 0 | 126,650 | 0 | 126,650 | 630 | 127,280 |
| Change in net unrealized gains on investments, net of taxes | 0 | 0 | 196,375 | 196,375 | 0 | 196,375 |
| Change in foreign currency translation adjustments, net of taxes | 0 | 0 | 1,903 | 1,903 | 186 | 2,089 |
| Change in net actuarial pension loss, net of taxes | 0 | 0 | 1,036 | 1,036 | 0 | 1,036 |
| Comprehensive income | 325,964 | 816 | 326,780 | |||
| Issuance of common stock | 6,664 | 0 | 0 | 6,664 | 0 | 6,664 |
| Repurchase of common stock | 0 | (42,080) | 0 | (42,080) | 0 | (42,080) |
| Restricted stock units expensed | 1,257 | 0 | 0 | 1,257 | 0 | 1,257 |
| Purchase of noncontrolling interest | (8,345) | 0 | 237 | (8,108) | (1,557) | (9,665) |
| Other | 0 | 0 | 0 | 0 | (510) | (510) |
| Balance at Sep. 30, 2010 | 872,452 | 1,598,968 | 586,637 | 3,058,057 | 16,103 | 3,074,160 |
| Balance at Dec. 31, 2010 | 884,457 | 1,735,973 | 551,093 | 3,171,523 | 16,169 | 3,187,692 |
| Net income | 0 | 91,850 | 0 | 91,850 | 4,329 | 96,179 |
| Change in net unrealized gains on investments, net of taxes | 0 | 0 | (19,235) | (19,235) | 0 | (19,235) |
| Change in foreign currency translation adjustments, net of taxes | 0 | 0 | (5,538) | (5,538) | 0 | (5,538) |
| Change in net actuarial pension loss, net of taxes | 0 | 0 | 1,080 | 1,080 | 0 | 1,080 |
| Comprehensive income | 68,157 | 4,329 | 72,486 | |||
| Issuance of common stock | 1,182 | 0 | 0 | 1,182 | 0 | 1,182 |
| Repurchase of common stock | 0 | (33,436) | 0 | (33,436) | 0 | (33,436) |
| Restricted stock units expensed | 4,606 | 0 | 0 | 4,606 | 0 | 4,606 |
| Acquisitions | 0 | 0 | 0 | 0 | 47,287 | 47,287 |
| Other | 148 | 0 | 0 | 148 | (1,873) | (1,725) |
| Balance at Sep. 30, 2011 | $ 890,393 | $ 1,794,387 | $ 527,400 | $ 3,212,180 | $ 65,912 | $ 3,278,092 |
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- Definition The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Increase in noncontrolling interest balance because of a business combination that occurred during the period.
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- Definition The increase (decrease) in accumulated comprehensive income during the period related to pension and other postretirement benefit plans, after tax. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total of Stockholders' Equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.
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- Definition Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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