Share-Based Compensation and Employee Ownership Plans Restricted Shares and Restricted Stock Units (Details) $ / shares in Units, $ in Millions			1 Months Ended	2 Months Ended	12 Months Ended
		Dec. 05, 2016	Mar. 31, 2016 shares	Jan. 31, 2014 shares	Dec. 31, 2016 USD ($) $ / shares shares		Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stockholders' Equity Note, Stock Split, Conversion Ratio		0.25
Equity Plans | Restricted Shares and Restricted Stock Units (RSUs)
Nonvested Restricted Shares and Restricted Stock Units
Balance outstanding, beginning of period, shares	[1]				5,370,091		4,413,646
Granted, shares	[1],[2]				2,157,403		2,260,901
Vested, shares	[1]				(1,487,092)		(1,047,072)
Canceled, shares	[1]				0		0
Forfeited, shares	[1]				(322,470)		(257,384)
Balance outstanding, end of period, shares	[1]				5,717,932	[2]	5,370,091
Weighted-Average Grant Date Fair Value
Balance outstanding, beginning of period, in dollars per share | $ / shares	[1]				$ 16.68		$ 14.80
Granted, in dollars per share | $ / shares	[1],[2]				14.02		17.96
Vested, in dollars per share | $ / shares	[1]				14.95		12.32
Canceled, in dollars per share | $ / shares	[1]				0.00		0.00
Forfeited, in dollars per share | $ / shares	[1]				14.89		13.68
Balance outstanding, end of period, in dollars per share | $ / shares	[1]				$ 16.23	[2]	$ 16.68
Unrecognized compensation expense | $					$ 60.6
Weighted-average recognition period for unrecognized compensation expense					2 years 5 months 25 days
Equity Plans | Performance based restricted stock
Nonvested Restricted Shares and Restricted Stock Units
Granted, shares			700,000	481,438
Forfeited, shares					(96,875)
Non-employee Director | Equity Plans | Restricted Stock Units (RSUs)
Nonvested Restricted Shares and Restricted Stock Units
Balance outstanding, end of period, shares					162,176
Weighted-Average Grant Date Fair Value
Granted, shares					56,100
Maximum
Nonvested Restricted Shares and Restricted Stock Units
Percent of RSU's earned					150.00%
Minimum
Nonvested Restricted Shares and Restricted Stock Units
Percent of RSU's earned					0.00%

[1] Share and per share amounts have been retroactively updated to reflect the one-for-four reverse stock split effective as of December 5, 2016.

[2] Performance linked restricted stock units of 481,438 were awarded to employees of the Company in December 2013 and January 2014. An additional 700,000 performance linked restricted stock units were awarded in March 2016. Of the awards granted, 96,875 have been forfeited through December 31, 2016. The remaining awards, included in the outstanding balance as of December 31, 2016, will vest between March 2019 and December 2020 and will be earned only to the extent that the Company attains specified market conditions relating to its volume-weighted average share price and total shareholder return in relation to certain benchmark indices and performance goals relating to aggregate net income and average return on shareholder equity. The actual number of RSUs ultimately earned could vary from 0, if performance goals are not met, to as much as 150% of the targeted award. Each RSU is equal to the one share of the Company’s Class A common stock. Compensation expense is recognized to the extent that it is probable that the Company will attain the performance goals.