Quarterly Financial Data (Unaudited) (Statement of Financial Condition) (Detail) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Quarterly Financial Information Disclosure [Abstract] | |||||||||||
| Revenues | $ 344,016 | $ 322,309 | $ 311,536 | $ 290,291 | $ 297,059 | $ 274,323 | $ 269,775 | $ 265,796 | $ 1,268,152 | $ 1,106,953 | $ 1,152,118 |
| Expenses | 344,095 | 317,649 | 310,286 | 294,961 | 294,435 | 281,162 | 271,302 | 272,124 | 1,266,991 | 1,119,023 | 1,163,868 |
| Income (loss) before item shown below | (79) | 4,660 | 1,250 | (4,670) | 2,624 | (6,839) | (1,527) | (6,328) | 1,161 | (12,070) | (11,750) |
| Change in fair value of contingent consideration | (67) | (3) | (63) | 152 | (38) | (72) | (49) | (57) | 19 | (216) | 55 |
| Income (loss) before income taxes | (146) | 4,657 | 1,187 | (4,518) | 2,586 | (6,911) | (1,576) | (6,385) | 1,180 | (12,286) | (11,695) |
| Net income (loss) | 6,634 | 3,402 | 1,325 | (3,679) | 621 | (7,515) | (17,801) | 2,384 | 7,682 | (22,311) | (11,213) |
| Loss attributable to noncontrolling interest | 10 | (3) | 3 | 5 | 9 | 1 | 14 | 18 | 15 | 42 | 62 |
| Net income (loss) attributable to the Company | 6,644 | 3,399 | 1,328 | (3,674) | 630 | (7,514) | (17,787) | 2,402 | 7,697 | (22,269) | (11,151) |
| Dividends declared on preferred stock | (8,456) | (8,149) | (7,953) | (7,924) | (7,924) | (7,780) | (7,389) | (7,345) | (32,482) | (30,438) | (28,108) |
| Net loss available to common shareholders | $ (1,812) | $ (4,750) | $ (6,625) | $ (11,598) | $ (7,294) | $ (15,294) | $ (25,176) | $ (4,943) | $ (24,785) | $ (52,707) | $ (39,259) |
| Basic loss per common share (in USD per share) | $ (0.01) | $ (0.02) | $ (0.03) | $ (0.06) | $ (0.04) | $ (0.08) | $ (0.14) | $ (0.03) | $ (0.13) | $ (0.29) | $ (0.21) |
| Diluted loss per common share (in USD per share) | $ (0.01) | $ (0.02) | $ (0.03) | $ (0.06) | $ (0.04) | $ (0.08) | $ (0.14) | $ (0.03) | $ (0.13) | $ (0.29) | $ (0.21) |
| Basic weighted average common shares (in shares) | 194,749,001 | 192,912,643 | 192,304,828 | 192,270,615 | 188,837,490 | 181,032,730 | 180,674,937 | 181,363,446 | 193,064,550 | 182,987,850 | 183,660,993 |
| Diluted weighted average common shares (in shares) | 194,749,001 | 192,912,643 | 192,304,828 | 192,270,615 | 188,837,490 | 181,032,730 | 180,674,937 | 181,363,446 | 193,064,550 | 182,987,850 | 183,660,993 |
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- Definition Increase Decrease In Fair Value Of Contingent Consideration No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No definition available.
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- Definition The amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders. No definition available.
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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