Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity - Narrative (Details)

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		121 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Dec. 31, 2016	Nov. 30, 2016	May 18, 2016	May 17, 2016	Nov. 30, 2014	Oct. 31, 2011	Mar. 31, 2007
Capital Unit [Line Items]
Shares authorized for repurchase (in shares) (up to)					10,000,000			10,000,000		2,500,000
Shares authorized for additional repurchase (in shares)									5,000,000
Repurchase and retirement of common stock (in shares)	115,000		17,615,000
Shares repurchased, value	$ 281		$ 44,971
Shares available for purchase (in shares)	9,885,000		9,885,000
Non-cash compensation expense	$ 1,429	$ 1,355
Shares surrendered for tax withholdings (in shares)	140,227
Preferred stock, shares authorized (in shares)	50,000,000		50,000,000	50,000,000		50,000,000	25,000,000
Common stock, shares authorized (in shares)	1,000,000,000		1,000,000,000	1,000,000,000		1,000,000,000	800,000,000
Options
Capital Unit [Line Items]
Unrecognized compensation cost for stock based compensation	$ 3,431		$ 3,431
Unrecognized compensation cost for stock based compensation, period of recognition	1 year 8 months 12 days
Purchase of shares (in shares)	171,096
Intrinsic value of options exercised	$ 106
Restricted shares
Capital Unit [Line Items]
Unrecognized compensation cost for stock based compensation	$ 7,331		7,331
Unrecognized compensation cost for stock based compensation, period of recognition	2 years 11 months 19 days
Restricted stock forfeited (in shares)	0
Restricted shares \| Employees
Capital Unit [Line Items]
Non-cash compensation expense	$ 1,418
Restricted shares \| Consultants and Independent Financial Advisors
Capital Unit [Line Items]
Non-cash compensation expense	11
Restricted shares \| Awards Granted in 2017
Capital Unit [Line Items]
Unrecognized compensation cost for stock based compensation	$ 3,298		$ 3,298
Unrecognized compensation cost for stock based compensation, period of recognition	3 years 9 months 13 days
Options, Warrants, and Other
Capital Unit [Line Items]
Shares surrendered for tax withholdings (in shares)	140,227
Series A Preferred Stock
Capital Unit [Line Items]
Preferred stock, shares authorized (in shares)	17,290,000		17,290,000	17,290,000
Dividends paid	$ 7,924
Dividends paid per share on monthly basis (in USD per share)	$ 0.1667