Other Income, net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other Income, net
Agency and commitment fees	$ (1,587)	$ (1,473)	$ (1,192)
Interest income	14,972	11,512	10,245
Other		70	(950)
Other income, net	$ 13,385	$ 10,109	$ 8,103