Stock Incentive Compensation and Employee Benefit Plans (Schedule of Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Weighted options outstanding:
Balance, Beginning of Period (shares)	767,830	408,212	767,830	828,092
Options granted (in shares)		0	0	0
Options forfeited (in shares)		0	0	0
Options expired (in shares)		0	0	0
Options exercised (in shares)		(201,417)	(359,618)	(60,262)
Balance, End of Period (shares)		206,795	408,212	767,830	828,092
Weighted average exercise price:
Weighted average exercise price, Beginning of Period (In dollars per share)	$ 48.71	$ 51.90	$ 48.71	$ 48.77
Options granted, Weighted average exercise price (In dollars per share)		0.00	0.00	0.00
Options forfeited, Weighted average exercise price (In dollars per share)		0.00	0.00	0.00
Options expired, Weighted average exercise price (In dollars per share)		0.00	0.00	0.00
Options exercised, Weighted average exercise price (In dollars per share)		50.59	45.09	49.52
Weighted average exercise price, End of Period (In dollars per share)		$ 53.17	$ 51.90	$ 48.71	$ 48.77
Weighted average remaining contractual life		10 months 24 days	1 year 7 months 6 days	2 years	2 years 10 months 24 days
Aggregate Intrinsic Value [Abstract]
Aggregate intrinsic value		$ 17,174	$ 25,020	$ 37,246	$ 40,221
Options exercised, Aggregate intrinsic value		$ 14,806	$ 21,205	$ 2,900
Range of Exercise Prices [Abstract]
Exercise price range, lower range limit (In dollars per share)		$ 50.71	$ 42.66	$ 37.51	$ 37.51
Exercise price range, upper range limit (In dollars per share)		59.66	$ 59.66	$ 59.66	$ 59.66
Total options exercisable, minimum (In dollars per share)		50.71
Total options exercisable, maximum (In dollars per share)		$ 59.66
Total options exercisable (in shares)		206,795
Total options exercisable, Weighted average exercise price (In dollars per share)		$ 53.17
Total options exercisable, Weighted average remaining contractual life		10 months 24 days
Total options exercisable, Aggregate intrinsic value		$ 17,174
Premium Option Plan Awards
Weighted options outstanding:
Balance, Beginning of Period (shares)	0	0	0	572,000
Options granted (in shares)	0	0		0
Options forfeited (in shares)		0	0	0
Options expired (in shares)		0	0	0
Options exercised (in shares)		0	0	(572,000)
Balance, End of Period (shares)		0	0	0	572,000
Weighted average exercise price:
Weighted average exercise price, Beginning of Period (In dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 73.62
Options granted, Weighted average exercise price (In dollars per share)	$ 0.00	0.00		0.00
Options forfeited, Weighted average exercise price (In dollars per share)		0.00	0.00	0.00
Options expired, Weighted average exercise price (In dollars per share)		0.00	0.00	0.00
Options exercised, Weighted average exercise price (In dollars per share)		0.00	0.00	73.62
Weighted average exercise price, End of Period (In dollars per share)		$ 0.00	$ 0.00	$ 0.00	$ 73.62
Weighted average remaining contractual life		0 years
Aggregate Intrinsic Value [Abstract]
Aggregate intrinsic value		$ 0	$ 0	$ 0	$ 13,567
Options exercised, Aggregate intrinsic value		$ 0	$ 0	$ 13,414
Range of Exercise Prices [Abstract]
Exercise price range, lower range limit (In dollars per share)		$ 0	$ 0	$ 0	$ 73.06
Exercise price range, upper range limit (In dollars per share)		0	$ 0	$ 0	$ 74.24
Total options exercisable, minimum (In dollars per share)		0
Total options exercisable, maximum (In dollars per share)		$ 0
Total options exercisable (in shares)		0
Total options exercisable, Weighted average exercise price (In dollars per share)		$ 0.00
Total options exercisable, Weighted average remaining contractual life		0 years
Total options exercisable, Aggregate intrinsic value		$ 0