Long-term Debt Narrative (Details) (USD $)		9 Months Ended		1 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended
	Feb. 26, 2013	Sep. 30, 2013 Senior Notes [Member] China Merchants Bank Co. (CMB) [Member]	May 13, 2013 Senior Notes [Member] China Merchants Bank Co. (CMB) [Member]	Mar. 31, 2010 Revolving Credit Facility [Member] China Merchants Bank Co. (CMB) [Member]	Sep. 30, 2013 Revolving Credit Facility [Member] China Merchants Bank Co. (CMB) [Member]	Mar. 31, 2010 Revolving Credit Facility [Member] China Merchants Bank Co. (CMB) [Member] Eurodollar Borrowing [Member]	Sep. 30, 2013 Revolving Credit Facility [Member] China Merchants Bank Co. (CMB) [Member] Eurodollar Borrowing [Member]
Long-term Debt and Interest Rate Caps (Textual) [Abstract]
Principal amount of debt			$ 175,000,000
Stated rate on debt			8.125%
Revolving line of credit, Maximum					175,000,000
Outstanding term loan indebtedness under Credit Facility					0
Debt instrument restrictive covenant, maximum percentage of stock to net income allowed to be repurchased					25.00%
Debt instrument basis spread on variable rate under option one					0.50%	3.50%	2.40%
Debt instrument basis spread on variable rate under option two					1.00%
Debt instrument basis spread on variable rate under option three				2.50%	1.40%
Fixed charge coverage ratio		2.0			1.125
Leverage ratio					3.25
Percentage of tangible net worth for covenants compliance				60.00%
Amount allowed by lender to invest in investee	$ 100,000,000