Share-Based Compensation Schedule of Restricted Stock Transactions (Details) - Restricted Stock [Member] - $ / shares	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested balance at beginning of period	1,426,453
Shares granted	1,373,300
Shares vested	(585,611)
Shares forfeited	(83,590)
Unvested balance at end of period	2,130,552
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted average grant date fair value, beginning of period	$ 31.02
Weighted average grant date fair value, grants	21.66	$ 31.63
Weighted average grant date fair value, vested	30.88
Weighted average grant date fair value, forfeited	27.54
Weighted average grant date fair value, end of period	$ 25.16