Fair Value of Financial Instruments (Reconciliation of Instrument with Unobservable Inputs) (Details) (Fair Value, Inputs, Level 3 [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Fair Value, Assets (Liabilities), Net Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance as of December 31, 2013	$ 43,847
Unrealized gain included in other comprehensive income, net	8,598
Changes in fair value included in net income, net	4,004
Purchases/issuances	147,591
Amortization included in net income, net	(3,065)
Ending balance as of June 30, 2014	200,975
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance as of December 31, 2013	60,583
Unrealized gain included in other comprehensive income, net	8,598
Changes in fair value included in net income, net	0
Purchases/issuances	151,197
Amortization included in net income, net	(3,065)
Ending balance as of June 30, 2014	217,313
Series D Preferred Stock Embedded Derivative [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance as of December 31, 2013	(16,736)
Unrealized gain included in other comprehensive income, net	0
Changes in fair value included in net income, net	5,216
Purchases/issuances	0
Amortization included in net income, net	0
Ending balance as of June 30, 2014	(11,520)
Contingent Consideration [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance as of December 31, 2013	0
Unrealized gain included in other comprehensive income, net	0
Changes in fair value included in net income, net	(1,212)
Purchases/issuances	(3,606)
Amortization included in net income, net	0
Ending balance as of June 30, 2014	$ (4,818)