Equity-Based Compensation - Performance Awards (Details) - Performance Shares - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Equity Instruments Other than Options, Beginning of Period (in shares)	1,627	2,224
Granted (in shares)	400	437
Forfeited or Expired (in shares)	(1)	(1)
Paid Out (in shares)	(861)	(1,033)
Equity Instruments Other than Options, End of Period (in shares)	1,165	1,627
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Beginning of Period (in USD per share)	$ 49.46	$ 43.24
Granted (in USD per share)	72.24	64.56
Forfeited or Expired (in USD per share)	41.02	53.16
Paid Out (in USD per share)	45.09	42.48
Weighted Average Grant Date Fair Value, End of Period (in USD per share)	$ 60.45	$ 49.46