Equity Textuals (Details) - USD ($) $ / shares in Units, $ in Thousands	2 Months Ended	12 Months Ended
	Feb. 13, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 31, 2015
Purchase of noncontrolling interest		$ 1,961	$ 2,075	$ 15,000
Preferred Stock, Shares Authorized		1,000,000
Common stock, shares authorized		500,000,000	500,000,000
Common stock, shares, issued		195,403,644	200,859,676
Common stock, shares outstanding		189,405,244	195,772,876
Treasury Stock, Shares, Acquired	1,969,289	8,811,847	12,455,281
Treasury Stock, Value, Acquired, Par Value Method	$ 57,100	$ 227,900	$ 345,300
Treasury Stock Acquired, Average Cost Per Share	$ 29.00	$ 25.87	$ 27.72
Stock Repurchase Program, Authorized Amount		$ 400,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 366,600
Dividends declared per share	$ 0.13	$ 0.51	$ 0.44	$ 0.34
Payments of Dividends, Common Stock		$ 98,418	$ 87,570	$ 71,517
Business Acquisition, Percentage of Voting Interests Acquired		11.00%			10.00%
Wilson Financial Group [Member]
Purchase of noncontrolling interest		$ 1,918