Goodwill and Intangible Assets (Schedule of Goodwill and Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Goodwill and Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 919	$ 0
Intangible Assets, Net (Excluding Goodwill)	24,273	14,693	25,852
Goodwill and Intangible Assets [Roll Forward]
Total goodwill, beginning of period	343,952
Total goodwill, end of period	343,952	115,554
CDI current period amortization	(1,580)	(1,029)
Total goodwill and intangible assets, end of period	368,225	130,247
Core Deposits [Member]
Goodwill and Intangible Assets [Line Items]
Estimated life of CDI, in years	10 years
Goodwill and Intangible Assets [Roll Forward]
Gross core deposit intangible balance, beginning of period			47,698	32,441
Accumulated amortization at beginning of period			(22,765)	(16,720)
Core deposit intangible, net, beginning of period	24,933	15,721
CDI current period amortization	(1,579)	(1,028)
Total core deposit intangible, end of period	$ 23,354	$ 14,693