Common Stock and Preferred Stock - Additional Information (Detail)		1 Months Ended					3 Months Ended		6 Months Ended		12 Months Ended
	Apr. 27, 2017 USD ($) shares	Jun. 30, 2017 USD ($) shares	Oct. 31, 2016 shares	Mar. 31, 2016 USD ($) shares	Jan. 31, 2016 USD ($) ExecutiveOfficers Director shares	Jun. 30, 2014 USD ($) shares	Jun. 30, 2017 USD ($) shares	Mar. 31, 2017 USD ($) ExecutiveOfficers Director shares	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Jun. 30, 2015 USD ($)
Class of Stock [Line Items]
Repurchase of common stock, shares | shares						3,112,840
Repurchase of common stock, value						$ 24,000,000
Repurchase of convertible senior notes									$ 35,614,000	$ 2,626,000
4.875% Convertible Senior Notes (due 2020)
Class of Stock [Line Items]
Amount of convertible notes repurchased and retired					$ 2,000,000
4.25% Convertible Senior Notes (due 2018)
Class of Stock [Line Items]
Amount of convertible notes repurchased and retired		$ 12,000,000					$ 12,000,000	$ 39,100,000	12,000,000		$ 6,100,000
Repurchase of convertible senior notes							11,600,000	24,100,000
Common Stock | 4.25% Convertible Senior Notes (due 2018)
Class of Stock [Line Items]
Amount of convertible notes repurchased and retired		$ 11,600,000					$ 11,600,000	$ 39,100,000	$ 11,600,000
Common stock shares issued upon conversion of debt instrument | shares		112,400					112,400	2,865,000
Common stock shares issued upon conversion of debt instrument, value		$ 400,000						$ 15,100,000
Common Stock | Hong Kong Meisheng Cultural Co
Class of Stock [Line Items]
Common stock issued, shares | shares	3,660,891
Common stock issued, value	$ 19,300,000
Securities
Class of Stock [Line Items]
Retirement of common stock (share) | shares											1,766,284	1,547,361
Retirement of common stock											$ 13,500,000	$ 13,200,000
Securities | 4.875% Convertible Senior Notes (due 2020)
Class of Stock [Line Items]
Amount of convertible notes repurchased and retired											2,000,000
Repurchase of convertible senior notes											1,900,000
Securities | 4.25% Convertible Senior Notes (due 2018)
Class of Stock [Line Items]
Amount of convertible notes repurchased and retired											6,100,000
Repurchase of convertible senior notes											$ 6,100,000
Maximum | Restricted Stock
Class of Stock [Line Items]
Vesting period									5 years
Maximum | Securities
Class of Stock [Line Items]
Stock repurchase, authorized amount													$ 35,000,000
Executive officer
Class of Stock [Line Items]
Restricted stock issued, shares | shares				134,058	449,120			873,787
Restricted stock issued, value				$ 900,000	$ 3,600,000			$ 4,500,000
Number of executive officers | ExecutiveOfficers					2			2
Executive officer | Restricted Stock
Class of Stock [Line Items]
Vesting period								3 years
Non-employee directors
Class of Stock [Line Items]
Restricted stock issued, shares | shares			2,463		62,710			94,102
Restricted stock issued, value					$ 500,000			$ 500,000
Number of non-employee directors | Director					5			5
Non-employee directors | Hong Kong Meisheng Cultural Co
Class of Stock [Line Items]
Restricted stock issued, shares | shares	13,319
Restricted stock issued, value	$ 100,000
Non-employee directors | Restricted Stock
Class of Stock [Line Items]
Shares of restricted stock, vesting date			2017-01		2017-01			2018-01
Non-employee directors | Restricted Stock | Hong Kong Meisheng Cultural Co
Class of Stock [Line Items]
Shares of restricted stock, vesting date	2018-01