Changes in Equity (Rollforward) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Balances	$ 2,777,459
Dividends declared	(111,435)
Share repurchases	(237,154)
Equity-based compensation	18,286
Comprehensive and net income (loss)	502,625
Balances	2,949,781
Common Stock
Balances	641
Balances	641
Treasury Stock
Balances	(416,829)
Share repurchases	(237,154)
Equity-based compensation	3,773
Balances	(650,210)
Additional Paid-In Capital
Balances	1,132,749
Equity-based compensation	14,714
Balances	1,147,463
Retained Earnings
Balances	2,210,459
Dividends declared	(111,435)
Equity-based compensation	(201)
Comprehensive and net income (loss)	508,008
Balances	2,606,831
Noncontrolling Interests
Balances	(149,561)
Comprehensive and net income (loss)	(5,383)
Balances	(154,944)
Redeemable Noncontrolling Interest
Balances	111,240
Balances	$ 111,240

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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