Borrowings (Credit Facility) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013
Line of Credit Facility [Line Items]
Amount outstanding	$ 6,300,000.0
Letters of credit outstanding	2,800,000
Remaining borrowing capacity	35,900,000
Revolving Line of Credit [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	45,000,000.0
Swing Line Loan [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	10,000,000.0
Senior Loans [Member] | IPO [Member]
Line of Credit Facility [Line Items]
Amount outstanding	$ 75,000,000.0
Minimum [Member]
Line of Credit Facility [Line Items]
Commitment fee on unused portion of facility	1.25%
Maximum [Member]
Line of Credit Facility [Line Items]
Commitment fee on unused portion of facility	0.25%
Secondary Rates [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.00%
Secondary Rates [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.75%
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.75%
Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.50%