Credit Facility (Details) (USD $)				0 Months Ended			0 Months Ended
	Mar. 31, 2014 Credit facility	Dec. 31, 2013 Credit facility	Mar. 30, 2012 Credit facility	Mar. 30, 2012 Credit facility LIBOR	Aug. 20, 2013 Credit Facility	Aug. 20, 2013 Credit Facility Maximum	Mar. 30, 2012 Below Threshold Credit facility LIBOR	Mar. 30, 2012 Above Threshold Credit facility LIBOR	Aug. 21, 2013 Line of Credit Facility, Interest Rate, Option One Credit facility Maximum LIBOR	Aug. 21, 2013 Line of Credit Facility, Interest Rate, Option One Credit facility Minimum LIBOR	Aug. 21, 2013 Line of Credit Facility, Interest Rate, Option Two Credit facility Maximum Base Rate	Aug. 21, 2013 Line of Credit Facility, Interest Rate, Option Two Credit facility Minimum Base Rate	Aug. 21, 2013 Line of Credit Facility, Base Rate, Option Two Credit facility Federal Funds Effective Rate	Aug. 21, 2013 Line of Credit Facility, Base Rate, Option Three Credit facility One-Month LIBOR	Dec. 23, 2013 Term Loan Credit facility	Aug. 20, 2013 Term Loan Credit facility	Dec. 23, 2013 Credit facility	Aug. 20, 2013 Credit facility
Line of Credit Facility [Line Items]
Maximum capacity on credit facility			$ 40,000,000.0		$ 220,000,000										$ 340,000,000	$ 110,000,000	$ 50,000,000	$ 110,000,000
Accordion feature of credit facility						325,000,000
Spread on variable rate basis				2.50%					2.75%	1.50%	1.75%	0.50%	0.50%	1.00%
Unused capacity fee percentage							0.20%	0.30%
Unused capacity commitment fee percentage threshold				50.00%
Revolving credit facility	305,000,000	305,000,000
Effective Interest Rate	2.18%	2.19%
Remaining borrowing capacity	$ 85,000,000