This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Value of stock issued as a result of the exercise of stock options.

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Changes in Equity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Increase (Decrease) in Equity
Balances	$ 2,795,527
Proceeds from exercise of stock options, including related tax effect	1,752
Dividends declared	(33,232)us-gaap_DividendsCommonStockCash
Distributions to noncontrolling investors	(29)
Equity-based compensation	5,781
Comprehensive income (loss)	26,954
Net income (loss)	26,954us-gaap_ProfitLoss	33,698us-gaap_ProfitLoss
Balances	2,796,753
Common Stock
Increase (Decrease) in Equity
Balances			635
Balances	635		635
Additional Paid-in Capital
Increase (Decrease) in Equity
Balances	1,083,435
Proceeds from exercise of stock options, including related tax effect	1,752
Equity-based compensation	3,418
Balances	1,088,605
Retained Earnings
Increase (Decrease) in Equity
Balances	2,227,843
Dividends declared	(33,232)
Equity-based compensation	(18)
Comprehensive income (loss)	30,761
Net income (loss)	30,761
Balances	2,225,354
Treasury Stock
Increase (Decrease) in Equity
Balances	(398,898)
Equity-based compensation	2,381
Balances	(396,517)
Noncontrolling Interests
Increase (Decrease) in Equity
Balances	(117,488)
Distributions to noncontrolling investors	(29)
Comprehensive income (loss)	(3,807)
Net income (loss)	(3,807)
Balances	(121,324)
Redeemable Noncontrolling Interest
Increase (Decrease) in Equity
Balances			126,340
Balances	$ 126,340		$ 126,340