Consolidated Statements of Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock Including Additional Paid in Capital [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2012	$ 603,102	$ 58,089	$ 78,744	$ 640,891	$ (176,746)	$ 2,124	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the Company	34,531	0	0	0	34,531	0	0
Other comprehensive income/ (loss), net of tax	5,205	0	0	0	0	5,205	0
Dividends paid to common shareholders	(7,954)	0	0	(7,954)	0	0	0
Dividends paid to preferred shareholders	(923)	0	0	(923)	0	0	0
Repurchase of Non-Cumulative Perpetual Contingent Convertible Preferred Stock, Series B	(69,827)	(58,089)	0	(11,738)	0	0	0
Issuance of 6.95% Non-Cumulative Perpetual Preferred Stock, Series D, net of issuance costs	47,754	47,754	0	0	0	0	0
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	135	0	0	0	0	0	135
Net proceeds from issuance of common stock	551	0	72	479	0	0	0
Issuance of shares through incentive stock grants, net of shares canceled or forfeited	0	0	667	(667)	0	0	0
Amortization of stock compensation and employee stock purchase plan	3,797	0	0	3,797	0	0	0
Stock options exercised	1,888	0	251	1,637	0	0	0
Tax deficiency from certain stock compensation awards	(643)	0	0	(643)	0	0	0
Other equity adjustments	2,071	0	0	2,071	0	0	0
Ending Balance at Jun. 30, 2013	609,277	47,754	79,734	626,950	(142,215)	(3,081)	135
Beginning Balance at Dec. 31, 2013	633,688	47,753	79,838	616,334	(106,211)	(4,197)	171
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to the Company	38,373	0	0	0	38,373	0	0
Other comprehensive income/ (loss), net of tax	(2,655)	0	0	0	0	(2,655)	0
Dividends paid to common shareholders	(12,786)	0	0	(12,786)	0	0	0
Dividends paid to preferred shareholders	(1,738)	0	0	(1,738)	0	0	0
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	61	0	0	0	0	0	61
Net proceeds from issuance of common stock	575	0	61	514	0	0	0
Issuance of shares through incentive stock grants, net of shares forfeited, canceled, or withheld for employee taxes, value	(925)	0	314	(1,239)	0	0	0
Amortization of stock compensation and employee stock purchase plan	2,578	0	0	2,578	0	0	0
Stock options exercised	1,419	0	181	1,238	0	0	0
Tax deficiency from certain stock compensation awards	585	0	0	585	0	0	0
Other equity adjustments	(1,834)	0	0	(1,834)	0	0	0
Ending Balance at Jun. 30, 2014	$ 662,651	$ 47,753	$ 80,394	$ 603,652	$ (67,838)	$ (1,542)	$ 232