Credit Facilities and Long-Term Debt - Credit Facility (Details) (USD $)	9 Months Ended
	Sep. 30, 2014
Line of Credit Facility [Line Items]
Expiration date	Mar. 31, 2019
Revolving credit facility, maturing March 2019
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 60,000,000
Remaining borrowing capacity	13,700,000
Revolving credit facility, maturing March 2019 | Minimum
Line of Credit Facility [Line Items]
Unused commitment fee, percent	0.25%
Revolving credit facility, maturing March 2019 | Maximum
Line of Credit Facility [Line Items]
Unused commitment fee, percent	0.50%
Revolving credit facility, maturing March 2019 | Base rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	4.75%
Revolving credit facility, maturing March 2019 | Base rate | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Revolving credit facility, maturing March 2019 | Base rate | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.50%
Revolving credit facility, maturing March 2019 | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.75%
Revolving credit facility, maturing March 2019 | LIBOR | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Revolving credit facility, maturing March 2019 | LIBOR | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.50%
Revolving credit facility, maturing March 2019 | UK Borrower
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 10,000,000